OPINION
PHILLIPS, Chief Justice.
In this original proceeding we must determine whether accident reports and witness statements prepared by Relator and its insurer following a plant explosion are privileged from discovery. We modify our decision in Flores v. Fourth Court of Appeals, 777 S.W.2d 38, 40-41 (Tex.1989), to hold that investigative documents are prepared in “anticipation of litigation” for purposes of Tex.R.Civ.P. 166b(3) if a) a reasonable person would have concluded from the totality of the circumstances surrounding the investigation that there was a substantial chance that litigation would ensue; and b) the party resisting discovery believed in good faith that there was a substantial chance that litigation would ensue and conducted the investigation for the purpose of preparing for such litigation. This approach will further the public policy underlying the investigatory privileges without unduly restricting discovery, as these privileges may be overcome where the requesting party demonstrates a substantial need for the materials and undue hardship in obtaining the substantial equivalent of the materials by other means. See Tex. R.Civ.P. 166b(3). Because we today alter the controlling law, we deny mandamus relief without prejudice to allow the trial court to reconsider its ruling in light of today’s opinion.
I
An explosion occurred on August 23, 1990, at a Wichita Falls manufacturing facility operated by the National Tank Company (NATCO), Relator in this proceeding. The explosion critically injured Rex Will-son, a NATCO employee, and two other persons employed by independent contractors. Willson later died from his injuries. Allen Pease, NATCO’s General Counsel and Secretary, learned of the explosion the day it occurred and dispatched Henry Townsend, NATCO’s safety and risk control coordinator, to investigate. Although not a lawyer, Townsend was employed in NATCO’s legal department under Pease’s supervision. Pease also immediately notified David Sneed, a brokerage supervisor with American International Adjustment Company (AIAC), a representative of NAT-CO’s liability insurers. Pease explained to Sneed the serious nature of the accident, and recommended that AIAC initiate its own investigation, which it did.
[196]*196Willson’s wife, individually and on behalf of her children and the estate, sued NAT-CO and several other defendants on January 15, 1991. Shortly thereafter, she requested that NATCO produce any reports prepared in connection with the accident investigation. NATCO objected, asserting the attorney-client, work-product, witness-statement, and party-communication privileges. In an order signed July 25, 1991, the trial court overruled NATCO’s objections as to documents prepared prior to October 25, 1990, the date NATCO learned that it had been sued by Frank Kroupa, one of the other persons injured in the explosion. The trial court thus ordered NATCO to produce the documents prepared prior to that date. These documents are 1) the transcripts of four -interviews of NATCO employees conducted by Henry Townsend shortly after the accident, 2) the transcripts of nine interviews of NATCO employees conducted by Phil Preeht, an AIAC employee, shortly after the accident, and 3) three accident reports prepared by Preeht and sent to Pease. The trial court, however, stayed the effect of this order to allow NATCO to seek mandamus relief.
NATCO first challenged the trial court’s discovery order by a mandamus action in the Court of Appeals. That court denied relief by an unpublished order on September 20, 1991. NATCO then sought mandamus relief here on September 27, 1991. While NATCO’s action was pending in this Court, the discovery dispute continued below regarding the depositions of Townsend and Don Hatfield, NATCO’s Operations Manager at the Wichita Falls plant. When these individuals were deposed concerning their post-accident conversations with NATCO plant personnel, NATCO objected on the basis of the same privileges previously asserted in response to plaintiff’s document requests. Consistent with its earlier ruling, the trial court by order signed November 15, 1991, held that these conversations were not privileged and ordered the depositions of Townsend and Hatfield to proceed “in line with the parameters placed upon the asserted privileges as set forth in this Court's order of July 25, 1991.” The trial court did not stay the effect of this second discovery order. NATCO therefore moved for emergency relief in the mandamus action already pending in this Court involving the document requests. In addition to the relief earlier requested, NATCO asked us to immediately stay the Townsend and Hatfield depositions, arguing that the sought-after testimony would moot the issues involved in the document requests. The Court granted emergency relief on November 19, 1991, staying both the depositions and the production of documents previously ordered by the trial court.
The parties opposing mandamus relief in this Court are Bonded Inspections, Inc. and Helm Inspection Services, Inc., the independent contractors that employed two of the injured individuals, and Stephen Cook, one of those injured. The members of Will-son’s family have settled their claims.
II
Mandamus will lie to correct a discovery error only if 1) the discovery order constitutes a clear abuse of discretion, and 2) the aggrieved party has no adequate remedy by ordinary appeal. Walker v. Packer, 827 S.W.2d 833, 839-840 (Tex. 1992). To determine whether the trial court abused its discretion, it is necessary to examine the scope of the privileges asserted by NATCO.
NATCO first argues that each of the documents is protected by the attorney-client privilege. This privilege protects:
confidential communications made for the purpose of facilitating the rendition of professional legal services to the client (1) between himself or his representative and his lawyer or his lawyer’s representative, (2) between his lawyer and the lawyer’s representative, (3) by him or his representative or his lawyer or a representative of the lawyer to a lawyer, or a representative of a lawyer representing another party in a pending action and concerning a matter of common interest therein, (4) between representatives of the client or between the client and a representative of the client, or (5) among [197]*197lawyers and their representatives representing the same client.
Tex.R.Civ.Evid. 503(b).
We first address the witness statements which Townsend took from NATCO employees and then gave to Pease. NAT-CO argues that these statements are privileged under category (2) above, as communications between the lawyer (Pease) and a representative of the lawyer (Townsend).
A “representative of the lawyer” for purposes of the attorney-client privilege includes “one employed by the lawyer to assist the lawyer in the rendition of professional legal services.” Tex.R.Civ.Evid. 503(a)(4)(i). Assuming without deciding that Townsend was Pease’s representative for purposes of this rule,1 the witness statements are not protected by the attorney-client privilege. These communications were in the first instance made by employees at the Wichita Falls plant to Townsend; the threshold issue is whether they were privileged at that stage. The fact that the statements were first made to Townsend as Pease’s representative, and then relayed to Pease, cannot provide greater protection than if the employees had made the statements directly to Pease.
NATCO argues that the initial communications from the employees to Townsend are protected under subdivision (1) of Rule 503(b), as communications between representatives of the client and a representative of the lawyer. We conclude based on the record before us, however, that the employees who were interviewed are not “representatives” of NATCO for purposes of the attorney-client privilege. Texas Rule of Civil Evidence 503(a)(2) provides as follows:
A representative of the client is one having authority to obtain professional legal services, or to act on advice rendered pursuant thereto, on behalf of the client.
This definition adopts the “control group” test previously recognized by many federal courts. See Steven Goode & M. Michael Sharlot, Article V: Privileges, in Texas Rules of Evidence Handbook, 20 Hous. L.Rev. 273, 290 (1983). This test was first recognized in City of Philadelphia v. Westinghouse Electric Corp., 210 F.Supp. 483 (E.D.Pa.), petition for mandamus and prohibition denied sub. nom., General Electric Co. v. Kirkpatrick, 312 F.2d 742 (3d Cir.1962), cert. denied, 372 U.S. 943, 83 S.Ct. 937, 9 L.Ed.2d 969 (1963), in which the court held that a corporation could claim the attorney-client privilege only as to statements made by employees “in a position to control or even to take a substantial part in a decision about any action which the corporation may take upon the advice of the attorney.” Id. at 485. Courts applying this test generally, protect only statements made by the upper echelon of corporate management. William K.C. Dip-pel, Comment, The Attorney-Client Privilege in the Corporate Context—Upjohn Co. v. United States, 35 Sw.L.J. 935, 939 (1981). See, e.g., Congoleum Indus., Inc. v. GAF Corp., 49 F.R.D. 82, 85 (E.D.Pa. 1969) (protection limited to corporate and division vice presidents), aff'd, 478 F.2d 1398 (3d Cir.1973); Garrison v. General Motors Corp., 213 F.Supp. 515, 518 (S.D.Cal.1963) (only communications of directors, officers, department heads, division managers, and division chief engineers protected). The control group test reflects the distinction between the corporate entity and the individual employee and is based on the premise that only an employee who controls the actions of the corporation can personify the corporation. Westinghouse, 210 F.Supp. at 485; see also Goode & Sharlot, supra, at 290; R. David White, Radiant Burners Still Radiating: Attorney-Client Privilege for the Corporation, 23 S.Tex. L.J. 293, 299 (1982).
NATCO correctly argues that the United States Supreme Court rejected the control group test in Upjohn Co. v. United States, 449 U.S. 383, 101 S.Ct. 677, 66 L.Ed.2d 584 [198]*198(1981).2 Prior to Upjohn, the federal courts had split between two different tests for applying the attorney-client privilege to corporations: 1) the control group test, and 2) the “subject matter” test, first recognized in Harper & Row Publishers, Inc. v. Decker, 423 F.2d 487 (7th Cir.1970), aff'd per curiam by an equally divided court, 400 U.S. 348, 91 S.Ct. 479, 27 L.Ed.2d 433 (1971). Under the subject matter test, an employee’s statement is deemed to be that of the corporation if:
the employee makes the communication at the direction of his superiors in the corporation and where the subject matter upon which the attorney’s advice is sought by the corporation and dealt with in the communication is the performance by the employee of the duties of his employment.
Id. at 491-92.
The Supreme Court in Upjohn concluded that the control-group test “overlooks the fact that the privilege exists to protect not only the giving of professional advice to those who can act on it but also the giving of information to the lawyer to enable him to give sound and informed advice.” Upjohn, 449 U.S. at 390, 101 S.Ct. at 683. The Court held that statements given by lower-level employees to the corporation’s attorney at the behest of corporate management were protected. Id. at 395, 101 S.Ct. at 685. Although rejecting the control group test, the Court refused to expressly adopt the subject matter test.3
The control group and subject matter tests represent alternative approaches to applying the corporate attorney-client privilege. Both are supported by legitimate policy rationales, and neither is without its critics. See Goode & Sharlot, supra, at 290-291; Glen Weissenberger, Toward Precision in the Application of the Attorney-Client Privilege for Corporations, 65 Iowa L.Rev. 899, 908-13 (1980); Dippel, supra at 940; The Supreme Court, 1980 Term, 95 Harv.L.Rev. 17, 273-80 (1981). In deciding this cause, however, we are not free to choose one over the other. Texas Rule of Civil Evidence 503, which was promulgated in November 1982, almost two years after the Upjohn decision, clearly adopts the control group test.4 Goode & Sharlot, supra, at 290; Note, Attorney-Client Privilege for Corporate Clients: The Control Group Test, 84 Harv.L.Rev. 424, 435 & n. 31 (1970) (discussing Proposed Federal Rule of Evidence 5-03, 46 F.R.D. 161, 249 (1969), which contained the identical test).
Despite the language of Rule 503(a)(2), NATCO argues that a lower-echelon employee may be a representative of the corporation if the employee speaks with the “blessing” of corporate management. This of course is the subject matter test, an approach clearly available, but not selected, when the Texas rules were drafted. NAT-CO relies on Hulen D. Wendorf et al., Texas Rules of Evidence Manual Y-33 (3d ed. 1991), where the authors contend that the privilege should apply “in the case of a corporate employee who is not a part of the ‘control group’ but who has been authorized to seek legal counsel on behalf of the corporation, just as it did in Upjohn.” In Upjohn, however, the employees were merely responding to a questionnaire from corporate counsel, not seeking legal counsel on behalf of the corporation. Upjohn, 449 U.S. at 394, 101 S.Ct. at 685. Likewise [199]*199in this case, the witnesses at the Wichita Falls plant, although they may have been speaking with management’s blessing, had not been authorized to seek legal counsel on behalf of the corporation.
There is no evidence in the record that the employees interviewed by Townsend were representatives of NATCO within the meaning of Texas Rule of Civil Evidence 503(a)(2). We therefore hold these witness statements are not protected by the attorney-client privilege.
For the same reason, the witness statements taken by Precht, the AIAC employee that investigated the explosion, are not protected by the attorney-client privilege. NATCO contends that Precht is NATCO’s representative under Rule 503(a)(2), and thus communications between Precht and Pease are privileged. As discussed below, there is no evidence to support the conclusion that Precht was NATCO’s representative. Even if he were, however, the witness statements taken by Precht and given to Pease would not be privileged since the witnesses who made the statements in the first place were not NATCO’s representatives. See Upjohn, 449 U.S. at 395-96, 101 S.Ct. at 685-86 (a client cannot cloak relevant information with a privilege merely by communicating it to the attorney).
We still must consider the reports prepared by Precht and sent to Pease. Unlike the witness statements, these reports are not transcripts of communications made by a third party, but rather constitute original communications from Precht to Pease. NATCO contends that the attorney-client privilege applies because Precht is a representative of NATCO under Rule 503(a)(2). NATCO notes that this rule contains no express requirement that the representative actually be employed by the client.
NATCO relies on Boring & Tunneling Co. of America v. Salazar, 782 S.W.2d 284, 289-90 (Tex.App.—Houston [1st Dist.] 1989, orig. proceeding), and Wiley v. Williams, 769 S.W.2d 715, 717 (Tex.App.—Austin 1989, orig. proceeding [leave denied] ). We do not find these opinions persuasive, however. The Wiley court held that correspondence between an attorney and the client’s insurer was protected by the attorney-client privilege simply because the correspondence constituted confidential communications made to facilitate the rendition of legal services, without considering whether the correspondence fell into one of the specific categories required under Rule 503(b). The Salazar court protected the correspondence under Rule 503(b)(1), without considering whether the adjuster was in fact a “representative” of the client for purposes of the attorney-client privilege.
We do not decide whether an employee of a liability insurer may ever be a “representative” of the insured under Rule 503(a)(2). Although the argument is not raised by NATCO, we note that liability policies typically vest the insurer with authority to hire counsel and conduct the defense of the insured. In such a case, certain employees of the insurer may qualify as representatives of the insured. However, under Rule 503(a)(2), the qualifying employees must be those actually having authority to hire counsel and to act on counsel’s advice on behalf of the insured. There is no indication in the record that Precht was such an employee. NATCO argues that “through David Sneed, [Precht] received and acted upon, the legal directions and advice of Allen Pease.” The thrust of NATCO’s argument is that because Precht was investigating the accident under the indirect supervision of Pease, he had the authority to act on Pease’s legal advice on behalf of NATCO. To the extent that Precht carried out Pease’s instructions, however, it was because he was required to do so pursuant to his employment duties. NATCO concedes that Precht was acting under David Sneed’s supervision. There is no indication that Precht acted on Pease’s instructions in the capacity of a legal client, with discretion to either accept or reject the legal advice. We therefore hold that the reports from Precht to Pease are not protected by the attorney-client privilege.
The trial court also held that post-accident conversations between NATCO [200]*200employees and Don Hatfield were not protected by the attorney-client privilege. Hatfield’s conversations with the NATCO plant personnel are not protected for the same reasons that the witness statements taken by Townsend are not protected: the plant personnel are not representatives of NATCO. Furthermore, the record does not establish that Hatfield is a representative of NATCO under Rule 503(a)(2). The record discloses only that Hatfield was “operations manager” at the Wichita Falls plant. NATCO offers no evidence as to whether this position vested Hatfield with authority to obtain professional legal services, or to act on advice rendered pursuant thereto, on behalf of NATCO. NATCO does argue that both Hatfield and Townsend had “authority to act on Mr. Pease’s legal advice (because it is undisputed) that the investigations they undertook were pursuant to the legal advice and instructions of Mr. Pease.” This is the same unconvincing argument that NATCO makes regarding Precht. The record reflects that Townsend and Hatfield were required by their job duties to follow the instructions of Pease, a corporate superior. They were not acting on Pease’s instructions in the capacity of a legal client.
Accordingly, we find no abuse of discretion by the trial court concerning its application of the attorney-client privilege.
III
We next consider whether the documents are privileged under Texas Rule of Civil Procedure 166b(3)(a) as “the work product of an attorney.” “Work product” has generally been defined as “specific documents, reports, communications, memoranda, mental impressions, conclusions, opinions, or legal theories, prepared and assembled in actual anticipation of litigation or for trial.” Wiley, 769 S.W.2d at 717; Brown & Root U.S.A., Inc. v. Moore, 731 S.W.2d 137, 140 (Tex.App.—Houston [14th Dist.] 1987, orig. proceeding); Evans v. State Farm Mut. Auto. Ins. Co., 685 S.W.2d 765, 767 (Tex.App.—Houston [1st Dist.] 1985, writ ref’d n.r.e.). NATCO argues, however, that the privilege is not limited to documents prepared in anticipation of litigation. This Court has not previously addressed this issue. To do so, it is necessary to examine some of the history of the work product privilege.
The work product doctrine was created by the United States Supreme Court in Hickman v. Taylor, 329 U.S. 495, 67 S.Ct. 385, 91 L.Ed. 451 (1947). In Hickman, five crew members drowned when the tugboat J.M. Stark sank in the Delaware River. The boat owner’s attorney investigated the accident, obtaining signed statements from some of the witnesses and making memo-randa of his conversations with the others. The estate of one of the deceased crew members subsequently sued the boat owner and sought by interrogatories to obtain copies of the witness statements and the attorney’s memoranda prepared during the investigation. The defendant objected on the grounds that the requests called “for privileged matter obtained in preparation for litigation” and was “an attempt to obtain indirectly counsel’s private files.” Id. at 499, 67 S.Ct. at 388.
The district court ordered production, but the United States Court of Appeals for the Third Circuit reversed and the Supreme Court affirmed the judgment of the appellate court. The Supreme Court could find no existing privilege that applied, but it created a new common law privilege for what it termed the “work product of the lawyer,” 5 consisting of interviews, memo-randa, briefs and other materials prepared “with an eye toward litigation.” Hickman, 329 U.S. at 511, 67 S.Ct. at 393. The Court justified the privilege as follows:
Proper preparation of a client’s case demands that [the attorney] assemble information, sift what he considers to be the relevant from the irrelevant facts, prepare his legal theories and plan his strategy without undue and needless interference. That is the historical and the nec[201]*201essary way in which lawyers act within the framework of our system of jurisprudence to promote justice and to protect their clients’ interests.
Id. The Court indicated that the privilege could be overcome as to factual information otherwise unavailable to the opposing party, but not as to the attorney’s “mental impressions.” Id. at 512, 67 S.Ct. at 394.
The Hickman work product doctrine was codified in Ped.R.Civ.P. 26(b)(3) in 1970.6 This rule maintains the distinction between ordinary work product, which is discoverable upon a showing of “substantial need” and “undue hardship,” and an attorney’s “mental impressions, conclusions, opinions, or legal theories,” which are discoverable, if at all, only upon a much higher showing.7 This latter category has come to be known as “opinion” or “core” work product. See In re Murphy, 560 F.2d 326, 329 n. 1 (8th Cir.1977); Jeff A. Anderson et al., Special Project, The Work Product Doctrine, 68 Cornell L.Rev. 760, 817-20 (1983). Federal Rule of Civil Procedure 26(b)(3) has been adopted verbatim by 34 states, and in substantial part by 10 others. See Elizabeth Thornburg, Rethinking Work Product, 77 Ya.L.Rev. 1515, 1520-21 (1991).
The structure of the Texas rule is somewhat different from the federal rule, however, as it simply protects the “work product of an attorney.” “Work product” is not defined in the rule, and this Court has never specifically defined the term.
It is important to note that the work product exemption has played a much lesser role in Texas than in the federal system and other states due to the separate privilege in Texas that protects communications between a party’s representatives. See Tex.R.Civ.P. 166b(3)(d). This privilege, which in one form or another has been part of the Texas Rules of Civil Procedure since their adoption in 1941, is broad enough to protect ordinary work prodúct. See Alex W. Albright, The Texas Discovery Privileges: A Fool’s Game?, 70 Tex.L.Rev. 781, 831 (1992). The specific work product exemption did not appear in the Texas Rules until 1973,8 and there was “a dearth of decisional law” interpreting this exemption prior to 1986, as the work product privilege was often merged with the party communication privilege. See James B. Sales, Pretrial Discovery in Texas Under the Amended Rules: Analysis and Commentary, 27 S.Tex.L.Rev. 305, 315 (1986). There appears to have been more reliance on the work product privilege since 1986, when the scope of the party communication privilege was narrowed.
NATCO relies on the plain language of Texas Rule of Civil Procedure 166b(3) in arguing that a document need not be prepared in anticipation of litigation to be privileged as work product. NATCO points out that Rule 166b(3)(c) and (d), the witness statement and party communication privileges, expressly require that the statement or communication be made in anticipation of litigation, while Rule 166b(3)(a), the work product privilege, contains no such [202]*202requirement. This argument, however, is unpersuasive. As discussed below, “work product” by definition applies only to materials prepared in anticipation of litigation.
As indicated, the work product doctrine was firmly established in federal case law and codified in the federal rules when it was adopted in Texas. There is nothing to indicate that the Texas concept of “work product” was intended to be different from that of the federal courts. See William W. Kilgarlin et al., Practicing Law in the “New Age”: The 1988 Amendments to the Texas Rules of Civil Procedure, 19 Tex. Tech.L.Rev. 881, 899 (1988). We have in the past looked to federal precedent in deciding work product questions. See Garcia v. Peeples, 734 S.W.2d 343, 348 (Tex. 1987).
There appears to be no doubt that the term “work product” in the federal courts, as well as the courts of other states, applies only to materials prepared in anticipation of litigation. See Fed.R.Civ.P. 26(b)(3),9 Hickman, 329 U.S. at 511, 67 S.Ct. at 393; United States v. El Paso Co., 682 F.2d 530, 542 (5th Cir.1982), cert. denied, 466 U.S. 944, 104 S.Ct. 1927, 80 L.Ed.2d 473 (1984); Litton Indus. v. Lehman Bros. Kuhn Loeb Inc., 125 F.R.D. 51, 54 (S.D.N.Y.1989); Sterling Drug Inc. v. Harris, 488 F.Supp. 1019, 1026 (S.D.N.Y. 1980); Miles v. Bell Helicopter Co., 385 F.Supp. 1029, 1033 (N.D.Ga.1974); Langdon v. Champion, 752 P.2d 999, 1005 (Alaska 1988); National Farmers Union Prop. & Casualty Co. v. District Court, 718 P.2d 1044, 1047 (Colo.1986) (en banc); LaMonte v. Personnel Bd., 581 So.2d 866, 868 (Ala.Civ.App.1991); Juneau v. Avoyelles Parish Police Jury, 482 So.2d 1022, 1031 (La.Ct.App.1986).
Texas courts of appeals have also uniformly held that the privilege applies only to materials prepared in anticipation of litigation. See Leede Oil & Gas, Inc. v. McCorkle, 789 S.W.2d 686, 687 (Tex.App.—Houston [1st Dist.] 1990, orig. proceeding); Star-Telegram, Inc. v. Schattman, 784 S.W.2d 109, 110 (Tex.App.—Fort Worth 1990, orig. proceeding); Toyota Motor Sales, U.S.A. v. Heard, 774 S.W.2d 316, 317 (Tex.App.—Houston [14th Dist.] 1989, orig. proceeding); Texas Dep’t of Mental Health and Mental Retardation v. Davis, 775 S.W.2d 467, 471 (Tex.App.—Austin 1989, orig. proceeding [leave denied]); Boring & Tunneling Co. v. Salazar, 782 S.W.2d at 286; Wiley v. Williams, 769 S.W.2d at 717; Southern Pac. Trans. Co. v. Banales, 773 S.W.2d 693, 694 (Tex. App.—Corpus Christi 1989, orig. proceeding); Axelson, Inc. v. McIlhany, 755 S.W.2d 170, 173 (Tex.App.—Amarillo 1988, orig. proceeding); Brown & Root, U.S.A., 731 S.W.2d at 140; Evans, 685 S.W.2d at 767.10
We therefore conclude that the term “work product” as used in Rule 166b(3)(a) applies only to materials prepared in anticipation of litigation. It is not necessary to further consider the scope of the work product exemption in Texas,11 because if [203]*203the disputed documents were prepared in anticipation of litigation, they are privileged under the witness statement and party communication privileges. We next consider those privileges.
IV
A
Texas Rule of Civil Procedure 166b(3)(c) protects from discovery witness statements “made subsequent to the occurrence or transaction upon which the suit is based and in connection with the prosecution, investigation, or defense of the particular suit, or in anticipation of the prosecution or defense of the claims made a part of the pending litigation....” Texas Rule of Civil Procedure 166b(3)(d) similarly protects communications between agents, representatives or employees of a party when made in anticipation of litigation. The only issue concerning the applicability of these privileges in this case is whether the witness statements and investigative reports generated by NATCO and its insurer were made in anticipation of litigation.
An investigation is conducted in anticipation of litigation if it meets the two-prong test of Flores v. Fourth Court of Appeals, 777 S.W.2d 38, 40-41 (Tex.1989). The first prong of the Flores test is objective. The court is required to determine whether a reasonable person, based on the circumstances existing at the time of the investigation, would have anticipated litigation. We stated in Flores that “[cjonsider-ation should be given to outward manifestations which indicate litigation is imminent.” Id. at 41 (emphasis added). Upon further consideration, however, we conclude that the “imminence” requirement impairs the policy goals of the witness statement and party communication privileges. Serving the function filled in many jurisdictions by the work product doctrine, these privileges seek to strike a balance between open discovery and the need to protect the adversary system. As the Supreme Court noted in Hickman, a party12 must be free to assemble information about the case free of undue interference from the other side:
Were such materials open to opposing counsel on mere demand, much of what is now put down in writing would remain unwritten. An attorney’s thoughts, heretofore inviolate, would not be his own. Inefficiency, unfairness and sharp practices would inevitably develop in the giving of legal advice and in- the preparation of cases for trial. The effect on the legal profession would be demoralizing. And the interests of the clients and the cause of justice would be poorly served.
Hickman, 329 U.S. at 511, 67 S.Ct. at 393-94. The investigative privileges promote the truthful resolution of disputes through the adversarial process by encouraging complete and thorough investigation of the facts by both sides. See Cohn, supra note 10, at 919-920; Anderson et al., supra, at 785; see also El Paso Co., 682 F.2d at 542; Coastal States Gas Corp. v. Department of Energy, 617 F.2d 854, 864 (D.C.Cir. 1980). At the same time, they do not unduly thwart discovery, as they are limited in scope and can be overcome by a showing of substantial need for the information and [204]*204undue hardship in obtaining it from other sources.
Considering these policies, we conclude that the objective prong of Flores is satisfied whenever the circumstances surrounding the investigation would have indicated to a reasonable person that there was a substantial chance of litigation. The confidentiality necessary for the adversary process is not defeated because a party, reasonably anticipating future litigation, conducts an investigation prior to the time that litigation is “imminent.” We accordingly modify Flores to the extent that it accords protection only to investigations conducted when litigation is imminent.
We agree with the dissenting justices’ characterization of “substantial chance of litigation.” This does not refer to any particular statistical probability that litigation will occur; rather, it simply means that litigation is “more than merely an abstract possibility or unwarranted fear.” 851 S.W.2d at 216. The underlying inquiry is whether it was reasonable for the investigating party to anticipate litigation and prepare accordingly.
The real parties in interest argue, and some courts of appeals have held, that the objective prong of Flores may be satisfied only where the plaintiff engages in some action indicating an intent to sue. See, e.g., Boring & Tunneling Co., 782 S.W.2d at 287. Flores, however, does not hold this. Rather, it requires the trial court to examine the totality of the circumstances to determine whether the investigation is conducted in anticipation of litigation. Flores, 777 S.W.2d at 41. Requiring that the plaintiff manifest an intent to sue would also be at odds with the policy goals of the witness statement and party communication privileges. These privileges are designed to promote the adversarial process by granting limited protection to investigations conducted in preparation for litigation. Common sense dictates that a party may reasonably anticipate suit being filed, and conduct an investigation to prepare for the expected litigation, before the plaintiff manifests an intent to sue. See Wiley 769 S.W.2d at 717; Smith v. Thornton, 765 S.W.2d 473, 477 (Tex.App.—Houston [14th Dist.] 1988, no writ); Lone Star Dodge, Inc. v. Marshall, 736 S.W.2d 184, 189 (Tex.App.—Dallas 1987, orig. proceeding).
We held in Stringer v. Eleventh Court of Appeals, 720 S.W.2d 801 (Tex. 1986), that “[t]he mere fact that an accident has occurred is not sufficient to clothe all post-accident investigations ... with a privilege." Id. at 802. We adhere to this holding, but we disapprove Stringer to the extent that it holds that the circumstances surrounding an accident can never by themselves be sufficient to trigger the privilege. If a reasonable person would conclude from the severity of the accident and the other circumstances surrounding it that there was a substantial chance that litigation would ensue, then the objective prong of Flores is satisfied.
The second prong of the Flores test is subjective. There, we held that the party invoking the privilege must have had “a good faith belief that litigation would ensue.” 777 S.W.2d at 41. For the reasons previously discussed with respect to the objective prong, however, we conclude that the subjective prong is properly satisfied if the party invoking the privilege believes in good faith that there is a substantial chance that litigation will ensue. It does not further the policy goals of the privilege to require the investigating party to be absolutely convinced that litigation will occur. Also, although not expressly stated in Flores, we believe that the subjective prong plainly requires that the investigation actually be conducted for the purpose of preparing for litigation. An investigation is not conducted “in anticipation of litigation” if it is in fact prepared for some other purpose. As with the objective prong, the court must examine the totality of the circumstances to determine whether the subjective prong is satisfied.
Most courts in other jurisdictions construing “anticipation of litigation” under Federal Rule of Civil Procedure 26(b)(3) and its state counterparts likewise do not require that plaintiff have manifested an intent to sue to trigger the privilege. [205]*205Rather, it is sufficient if the circumstances indicate that the materials were prepared because of the prospect of litigation. See, e.g., Binks Mfg. Co. v. National Presto Indus., Inc., 709 F.2d 1109, 1120 (7th Cir. 1983); El Paso Co., 682 F.2d at 542; In re Grand Jury Proceedings, 604 F.2d 798, 803 (3d Cir.1979); Diversified Indus., Inc. v. Meredith, 572 F.2d 596, 604 (8th Cir. 1977); Litton Indus., 125 F.R.D. at 54; Winter Panel Corp. v. Reichhold Chems., Inc., 124 F.R.D. 511, 513-14 (D.Mass.1989); Anderson v. Torrington Co., 120 F.R.D. 82, 86 (N.D.Ind.1987); State ex rel. Corbin v. Weaver, 140 Ariz. 123, 680 P.2d 833, 839 (Ariz.Ct.App.1984); Mullins v. Vakili, 506 A.2d 192, 197-98 (Del.Super.Ct.1986); American Bldgs. Co. v. Kokomo Grain Co., 506 N.E.2d 56, 62-63 (Ind.Ct.App. 1987); Ashmead v. Harris, 336 N.W.2d 197, 200 (Iowa 1983); Kaarup v. St. Paul Fire & Marine Ins. Co., 436 N.W.2d 17, 21 (S.D.1989). It is not necessary that litigation be threatened or imminent, as long as the prospect of litigation is identifiable because of claims that have already arisen. See Hercules Inc. v. Exxon Corp., 434 F.Supp. 136, 151 (D.Del.1977); United States v. Exxon Corp., 87 F.R.D. 624, 638 (D.D.C.1980); Great Lakes Concrete Pole Corp. v. Eash, 148 Mich.App. 649, 385 N.W.2d 296, 298 n. 2 (1986); United States v. Bonnell, 483 F.Supp. 1070, 1078 (D.Minn.), modified on other grounds, 483 F.Supp. 1091 (D.Minn.1979).
The fundamental problem that has plagued other courts is determining whether a “routine” investigation is conducted in anticipation of litigation. The Advisory Committee Notes to the 1970 federal rules amendments provide that “[m]aterials assembled in the ordinary course of business, or pursuant to public requirements unrelated to litigation, or for other nonlitigation purposes” are not protected. Proposed Amendments to the Federal Rules of Civil Procedure Relating to Discovery, 48 F.R.D. 485, 501 (1970). Accordingly, many courts have recognized a bright-line “ordinary course of business” exception.
For example, in Miles v. Bell Helicopter Co., 385 F.Supp. 1029 (N.D.Ga.1974), the court compelled discovery of defendant’s investigation of a fatal helicopter crash. The court found that “defendants routinely have such reports prepared when injuries are sustained in the crash of one of the helicopters they manufactured,” id. at 1032, and therefore the reports were prepared in the ordinary course of business and not in anticipation of litigation. The court rejected defendant’s argument that the privilege should apply because helicopter crashes causing serious injury routinely give rise to litigation. Id. See also Soeder v. General Dynamics Corp., 90 F.R.D. 253, 255 (D.Nev.1980); McDougall v. Dunn, 468 F.2d 468, 473 (4th Cir.1972); Thomas Organ Co. v. Jadranska Slobodna Plovidba, 54 F.R.D. 367, 372-373 (N.D.Ill.1972); Atlanta Coca-Cola Bottling Co. v. Transamerica Ins. Co., 61 F.R.D. 115, 118 (N.D.Ga.1972); Sterling Drug, 488 F.Supp. 1019, 1026 (S.D.N.Y. 1980); National Farmers Union Property and Casualty Co. v. District Court, 718 P.2d 1044, 1047-48 (Colo.1986) (en banc); Henry Enters., Inc. v. Smith, 225 Kan. 615, 592 P.2d 915, 921 (1979); Langdon v. Champion, 752 P.2d 999, 1006-07 (Alaska 1988).
Other courts, however, have rejected a hard and fast ordinary course of business exception, recognizing that a prudent party may routinely prepare for litigation after a serious accident. See Ashmead, 336 N.W.2d at 200 (“It does not matter that the investigation is routine. Even a routine investigation may be made in anticipation of litigation.”) (citations omitted); Harriman v. Maddocks, 518 A.2d 1027, 1034 (Me.1986). In holding that an insurer’s routine post-accident investigation was privileged, the court in Fireman’s Fund Ins. Co. v. McAlpine, 120 R.I. 744, 391 A.2d 84, 89-90 (1978), concluded as follows:
In our litigious society, when an insured reports to his insurer that he has been involved in an incident involving another person, the insurer can reasonably anticipate that some action will be taken by the other party. The seeds of prospective litigation have been sown, and the prudent party, anticipating this fact, will begin to prepare his case.... Although [206]*206a claim may be settled short of the instigation of legal action, there is an ever-present possibility of a claim’s ending in litigation. The recognition of this possibility provides, in any given case, the impetus for the insurer to garner information regarding the circumstances of a claim.
See also Almaguer v. Chicago, Rock Island & Pac. R.R., 55 F.R.D. 147, 149 (D.Neb.1972). The McAlpine court made clear that routine post-accident investigations would not always be privileged, as “[i]n many cases an insurer may prepare reports for a purpose other than in response to the threat of litigation.” McAlpine, 391 A.2d at 90.
Most commentators disapprove of a bright-line ordinary course of business exception. See Anderson et al., supra, at 852 (“[A] court should treat the ordinary course of business criterion as merely one factor among many when applying the anticipation-of-litigation test.”); Albright, supra, at 845 (“Although it is true that a document routinely prepared for business purposes other than litigation is less likely to have been prepared in anticipation of litigation, it is not true that every investigation conducted on a routine basis is conducted for purposes other than litigation.”); Robert H. Oberbillig, Note, Work Product Discovery: A Multifactor Approach to the Anticipation of Litigation Requirement in Federal Rule of Civil Procedure 26(b)(3), 66 Iowa L.Rev. 1277, 1294-95 (1981) (arguing that excluding documents prepared in the ordinary course of business from protection “overlookfs] the possibility that the ordinary course of business developed out of a desire to adequately prepare for future litigation”).
We agree that there should be no bright-line ordinary course of business exception. It may very well be that a party routinely investigates serious accidents because such accidents routinely give rise to litigation. As with other investigations, an investigation performed in the ordinary course of business is conducted in anticipation of litigation if it passes both prongs of the Flores test. With regard to the subjective prong, the circumstances must indicate that the investigation was in fact conducted to prepare for potential litigation. The court therefore must consider the reasons that gave rise to the company’s ordinary business practice. If a party routinely investigates accidents because of litigation and nonlitigation reasons, the court should determine the primary motivating purpose underlying the ordinary business practice. See United States v. Davis, 636 F.2d 1028, 1040 (5th Cir. Unit A Feb.1981); Schaffer v. Rogers, 362 N.W.2d 552, 555 (Iowa 1985); LaMonte v. Personnel Board of Jefferson County, 581 So.2d 866, 868 (Ala.App.1991). Cf. GAF Corp. v. Eastman Kodak Co., 85 F.R.D. 46, 51 (S.D.N.Y.1979) (document that was prepared “at least in part” to prepare for litigation was privileged).13
[207]*207In summary, an investigation is conducted in anticipation of litigation for purposes of Rule 166b(3) when a) a reasonable person would have concluded from the totality of the circumstances surrounding the investigation that there was a substantial chance that litigation would ensue; and b) the party resisting discovery believed in good faith that there was a substantial chance that litigation would ensue and conducted the investigation for the purpose of preparing for such litigation.
B
Normally in a mandamus proceeding such as this, we would next determine whether the trial court abused its discretion in determining that the post-accident investigation was not conducted in anticipation of litigation. In this case, however, as we have modified the controlling legal standard, we believe that the trial court should have an opportunity to reconsider its conclusion in light of today’s opinion. We therefore conclude that the writ of mandamus should be denied without prejudice14 to allow the trial court to reconsider NAT-CO’s objections based on the witness statement and party communication privileges.
y
We next consider whether NATCO has an adequate remedy by appeal. We concluded in Walker that the remedy by appeal is not adequate when the trial court erroneously orders disclosure of privileged information which will materially affect the rights of the aggrieved party. 827 S.W.2d at 843. Most of the documents at issue here are statements of witnesses to the explosion taken shortly after it occurred. The information in these statements obviously could have a significant impact on the assignment of liability. NATCO therefore has no adequate remedy by appeal.
For the foregoing reasons, the writ of mandamus is denied without prejudice to allow the trial court to reconsider NATCO’s objections based on the witness statement and party communication privileges in light of today’s opinion. The stay order previously issued by this Court remains in effect only so long as necessary to allow the trial court to act. The trial court may in its discretion lift the stay when it deems appropriate.