Peters, C. J.
The dispositive issue in this case, which comes to us by way of reservation, is whether General Statutes (Rev. to 1989) § 10-145b (i)1 violates the plain[288]*288tiffs’ due process and contractual rights guaranteed by the federal and state constitutions. The plaintiffs, the Connecticut Education Association, Inc., the Connecticut State Federation of Teachers, Phyllis Greene and Harriet Strain, brought suit in the Superior Court seeking a declaratory judgment that General Statutes (Rev. to 1989) § 10-145b (i) is unconstitutional. The trial court granted the parties’ motion for reservation to the Appellate Court upon stipulated facts to determine the provision’s constitutionality. We transferred the case here pursuant to Practice Book § 4023 and now answer the reserved question2 in the negative.
Pursuant to Practice Book § 4148, the parties stipulated to the following facts. The plaintiffs, the Connecticut Education Association, Inc., and the Connecticut State Federation of Teachers, Inc., are nonprofit corporations and labor organizations representing public school teachers and local teacher bargaining representatives pursuant to General Statutes § 10-153a. The plaintiff [289]*289Phyllis Greene resides in Portland, teaches in the Portland public school system and holds a standard teaching certificate issued by the state department of education. The plaintiff Harriet Strain resides in Killingworth, teaches in Old Saybrook and holds a permanent teaching certificate also issued by the state department of education. The defendant Gerald Tirozzi, the state commissioner of education, and the defendant state board of education (board) are jointly charged with the general supervision and control of the state’s educational interests. See General Statutes §§ 10-1, 10-3a and 10-4.
Several statutes provide a frame of reference for the issues in this case. General Statutes (Rev. to 1989) § 10-145,3 enjoins local boards of education from employing or paying any teacher who does not hold an appropriate state-issued teaching certificate. See Ames v. Board of Education, 167 Conn. 444, 446, 356 A.2d 100 (1975). Related statutes confer upon the defendant board the responsibility for issuing teaching certificates and adopting certificate regulations. General Statutes (Rev. to 1989) §§ 10-144o, 10-145a (a), 10-145d (a) and 10-146b.
Before May, 1986, a two-tiered certification process governed Connecticut school teachers. Newly certified teachers received “provisional teaching certificates,” valid for no fewer than three years. Thereafter, teachers became eligible to receive a “standard teaching certificate,” valid for life and revocable only “for cause,” as provided by statute. General Statutes (Rev. to 1985) [290]*290§ 10-144o; General Statutes (Rev. to 1989) § 10-145b (m);4 Ames v. Board of Education, supra, 446.
On July 2, 1986, the General Assembly passed the legislation presently at issue, Public Acts, Spec. Sess., May, 1986, No. 1, entitled “An Act Concerning Education Enhancement” (act). The act, as amended by Public Acts 1988, No. 88-273, replaced the two-tiered certificate system with a three-tiered system, beginning with an “initial educator certificate,” graduating to a “provisional educator certificate” and finally to a “professional educator certificate.” General Statutes (Rev. to 1989) § 10-144o (2), (5) and (7).5 To remain cer[291]*291tified to teach, those teachers holding standard or permanent teaching certificates must, by July 1, 1989, exchange them for professional educator certificates. The standard or permanent teaching certificates will be invalid after July 1, 1989. General Statutes (Rev. to 1989) § 10-145b (i). Thus, by July 1,1989, over 30,000 active teachers must surrender their teaching certificates.
The new professional educator certificates will be issued for five year renewable terms. The act, however, conditions the renewal of the certificates solely upon each teacher’s “successful completion of professional development activities which shall consist of not less than nine continuing education units [CEUs] or their equivalent . . . during each successive five-year period.” General Statutes (Rev. to 1989) § 10-145b (l) (l).6 The act requires state and local or regional [292]*292boards of education to underwrite the entire cost of CEU offerings.7 As the plaintiffs conceded at oral argument before this court, the only burden that the act imposes upon teachers already holding standard or permanent teaching certificates is the successful completion of the CEUs.
The provisions for the exchange of certificates and for the continuing education were enacted as part of a comprehensive legislative package intended to upgrade public education in this state. A major purpose of the act was to attract a greater number of qualified people to enter and to remain in the teaching profession. Recognizing the importance of higher salaries to the achievement of this goal, the legislature offered state money to each local and regional school district so that new teachers could be hired at a “state designated target minimum salary.” General Statutes (Rev. to 1989) §§ 10-257a (e), 10-257b. Further funding was provided to school districts so that they could increase the salaries of experienced teachers, address the problem of crowded classrooms, provide mentor and assessment programs and otherwise enhance their general educational offerings. General Statutes (Rev. to 1989) §§ 10-257c, 10-257d and 10-2571 In return for these financial enhancements of the teaching profes[293]*293sion as a whole, individual teachers are being required to improve their own teaching skills by completing nine CEUs within five teaching years after they receive their new professional educator certificates in July, 1989. The plaintiffs claim that the mandatory substitution of these certificates for the teaching certificates they presently hold will violate their constitutional rights to due process and to protection of contracts.
I
The plaintiffs make two separate due process arguments: procedural and substantive. We conclude that the act does not violate the plaintiffs’ due process rights in either respect.
A
Analysis of the plaintiffs’ procedural due process claim requires a three part inquiry: (1) did the plaintiffs have a property interest in their standard and permanent teaching certificates; (2) does General Statutes (Rev. to 1989) § 10-145b (i) deprive them of that property interest; and (3) did the deprivation of the interest occur without due process of law?8 Although we agree with the plaintiffs that they have a property interest that is constitutionally cognizable, we conclude that this interest has not been unconstitutionally impaired.
[294]*294“Property” is a “broad and majestic” term and a great constitutional concept “ ‘purposely left to gather meaning from experience.’ ” Board of Regents v. Roth, 408 U.S. 564, 571, 92 S. Ct. 2701, 33 L. Ed. 2d 548 (1972), quoting National Mutual Ins. Co. v. Tidewater Transfer Co., 337 U.S. 582, 646, 69 S. Ct. 1173, 93 L. Ed. 1556 (1949) (Frankfurter, J., dissenting). Property interests are more than abstract needs, desires or unilateral expectations of benefits or privileges. Rather, a person must have “a legitimate claim of entitlement” to a benefit or privilege to have a property interest in that benefit. Board of Regents v. Roth, supra, 577. “Property interests are not created by the Constitution, ‘they are created and their dimensions are defined by existing rules or understandings that stem from an independent source such as state law . . . . ’ ” Cleveland Board of Education v. Loudermill, 470 U.S. 532, 538, 105 S. Ct. 1487, 84 L. Ed. 2d 494 (1985), quoting Board of Regents v. Roth, supra, 577; see also Paul v. Davis, 424 U.S. 693, 709, 96 S. Ct. 1155, 47 L. Ed. 2d 405, reh. denied, 425 U.S. 985, 96 S. Ct. 2194, 48 L. Ed. 2d 811 (1976). “The hallmark of property . . . is an individual entitlement grounded in state law, which cannot be removed except ‘for cause.’ ” Logan v. Zimmerman Brush Co., 455 U.S. 422, 430, 102 S. Ct. 1148, 71 L. Ed. 2d 265 (1982). A person has an entitlement in a benefit or privilege if there are “rules or mutually explicit understandings that support his claim of entitlement to the benefit . . . that he may invoke at a hearing.” Perry v. Sinderman, 408 U.S. 593, 601, 92 S. Ct. 2694, 33 L. Ed. 2d 570 (1972); see also Bishop v. Wood, 426 U.S. 341, 344, 96 S. Ct. 2074, 48 L. Ed 2d 684 (1976); Bartlett v. Krause, 209 Conn. 352, 362-63, 551 A.2d 710 (1988); 2 R. Rotunda, J. Nowak & J. Young, Constitutional Law: Substance and Procedure (1986) § 17.5, pp. 234-36.
[295]*295Under the governing statutes and case law, the rights of Connecticut school teachers in their teaching certificates qualify as a property interest because these certificates are needed in order to obtain and maintain a teaching position. General Statutes (Rev. to 1989) § 10-145. Connecticut law provided, prior to the act at issue, that the defendant board could only revoke a teacher’s certificate “for cause,” as defined specifically by statute. General Statutes § 10-145b (m).9 Accordingly, we have expressly held that “[a] teacher who is given by statute the right to continued employment except upon a showing of cause or the bona fide elimination of his position . . . acquires a property right that is entitled to protection under the due process clause.” Lee v. Board of Education, 181 Conn. 69, 72, 434 A.2d 333 (1980). Our holding in Lee readily encompasses the proposition that teachers also have a property interest in the rights that inhere in the underlying certificates guaranteeing their employment. “Once licenses are issued . . . their continued possession may become essential in the pursuit of a livelihood. ... In such cases the licenses are not to be taken away without that procedural due process required by the Fourteenth Amendment.” Bell v. Burson, 402 U.S. 535, 539, 91 S. Ct. 1586, 29 L. Ed. 2d 90 (1971) (driver’s license of a clergyman whose ministry required travel by car); see also Pet v. Department of Health Services, 207 Conn. 346, 353-54, 542 A.2d 672 (1988) (license to practice medicine); Leib v. Board of Examiners for Nursing, 177 Conn. 78, 83, 411 A.2d 42 (1979) (registered nurse’s license); Hart Twin Volvo Corporation v. Commissioner of Motor Vehicles, 165 Conn. 42, 45, 327 A.2d 588 (1973) (license to sell and repair automobiles).
[296]*296The conclusion that the plaintiffs have a constitutionally protected property interest in their certificates does not of course establish that these property rights have been unconstitutionally compromised by the enactment of General Statutes (Rev. to 1989) § 10-145b (i). It bears repeating that, on July 1,1989, the plaintiffs’ new certificates will afford them the very same rights they had before the act’s passage except that they will have to complete nine CEUs, or their equivalent, within five teaching years, in order to renew their certificates for another five years.
Significantly, the plaintiffs do not contend that the constitution prevents the state, or even a local or regional school board, from imposing additional educational requirements as a condition for continued service as a teacher. Federal cases support the proposition that such educational requirements do not create an unconstitutional burden. “ ‘[LJegislation readjusting rights and burdens is not unlawful solely because it upsets otherwise settled expectations.’ ” United States v. Locke, 471 U.S. 84, 104, 105 S. Ct. 1785, 85 L. Ed. 2d 64 (1985), quoting Usery v. Turner Elkhorn Mining Co., 428 U.S. 1, 16, 96 S. Ct. 2882, 49 L. Ed. 2d 752 (1976). Furthermore, “[e]ven with respect to vested property rights, a legislature generally has the power to impose new regulatory constraints on the way in which those rights are used, or to condition their continued retention on performance of certain affirmative duties. As long as the constraint or duty imposed is a reasonable restriction designed to further legitimate legislative objectives, the legislature acts within its powers in imposing such new constraints or duties.” United States v. Locke, supra, 104; see also Brown v. McGarr, 774 F.2d 777, 782 (7th Cir. 1985) (completion of qualifying units a valid condition for admittance to the “trial bar,” even for an attorney who had already been a member of the bar before the creation of the [297]*297“trial bar”). The plaintiffs implicitly concede, therefore, that the legislature could constitutionally have subjected their existing teacher certificates to divestment, under § 10-145b (m) or otherwise, should they fail to complete the nine CEUs within five teaching years.
The explicit focus of the plaintiffs’ constitutional argument is their dissatisfaction with the statutory mandate that they trade lifetime certificates for renewable ones. We are not persuaded that the difference between the existing standard and permanent teaching certificates and the prospective professional educator certificate is a distinction of constitutional dimension, when completion of the educational requirement is the only statutory condition for renewal of the new certificates. The plaintiffs, in effect, argue that although an added educational requirement may operate constitutionally as a condition subsequent to the continuing validity of an existing teaching certificate, the identical requirement becomes unconstitutional when it is a condition precedent to renewal of a new certificate. Our reading of the relevant constitutional cases discloses no support for this proposition. See, e.g., Rogers v. Bellei, 401 U.S. 815, 833-34, 91 S. Ct. 1060, 28 L. Ed. 2d 499 (1971); Ramos-Hernandez v. Immigration & Naturalization Service, 566 F.2d 638, 642 (9th Cir. 1977). Taking into account the legislature’s laudable objective of upgrading education, we conclude that the act does not constitute a significant present impairment or deprivation of the plaintiffs’ property interests in their teaching certificates, and therefore does not violate their procedural due process rights.10
[298]*298Even were we to find that the act unconstitutionally impairs the plaintiffs’ property interests, “ ‘the question remains what process is due’ ”? Federal Deposit Ins. Corporation v. Mallen, 486 U.S. 230, 240, 108 S. Ct. 1780, 100 L. Ed. 2d 265 (1988); Morrissey v. Brewer, 408 U.S. 471, 481, 92 S. Ct. 2593, 33 L. Ed. 2d 484 (1972). The “root requirement” of the due process clause is that the state actor afford individuals notice and an opportunity for a hearing before depriving them of their property interests. Cleveland Board of Education v. Loudermill, supra, 542; Boddie v. Connecticut, 401 U.S. 371, 379, 91 S. Ct. 780, 28 L. Ed. 2d 113 (1971); Bartlett v. Krause, supra, 372. Although the defendants concede that there was no hearing at which individual teachers had the opportunity to protest the termination of their existing certificates, the legislature provided the plaintiffs with all the process that is their constitutional due. “In altering substantive rights through enactment of rules of general applicability, a legislature generally provides constitutionally adequate process simply by enacting the statute, publishing it, and, to the extent the statute regulates private conduct, affording those within the statute’s reach a reasonable opportunity both to familiarize themselves with the general requirements imposed and to comply with those requirements.” United States v. Locke, supra, 108; Texaco, Inc. v. Short, 454 U.S. 516, 532, 102 S. Ct. 781, 70 L. Ed. 2d 738 (1982). In this case the proposed act had been much publicized and the plaintiffs had not only been afforded “a reasonable opportunity to familiarize themselves” with it, but the two plaintiff unions, which also represent the individual plaintiffs, participated in the committee hearings leading up to the act. See Conn. Joint [299]*299Standing Committee Hearings, Education, Pt. 1,1986 Sess., pp. 156-62, 169-70,172-74 and 206-208. Thus, the legislature accorded to the plaintiffs all the process they were due.
B
We also disagree with the plaintiffs’ claim that the act violates their constitutional rights to substantive due process.11 The plaintiffs do not belong to a constitutionally recognized suspect class and they have not alleged the impairment of a fundamental constitutional right.12 Their claim must be tested, therefore, in accordance with the rules that normally govern constitutional challenges of economic or social welfare legislation, by ascertaining whether the legislature has acted arbitrarily or irrationally.
Constitutional attacks on the rationality of economic or social welfare legislation must rebut the presumption of constitutionality that attaches to such legislation. “ ‘[T]he burden is on one complaining of a due process violation to establish that the legislature has acted in an arbitrary and irrational way.’ ” Duke Power Co. v. Carolina Environmental Study Group, Inc., 438 [300]*300U.S. 59, 83, 98 S. Ct. 2620, 57 L. Ed. 2d 595 (1978), quoting Usery v. Turner Elkhorn Mining Co., supra, 15; see also Blue Sky Bar, Inc. v. Stratford, 203 Conn. 14, 28, 523 A.2d 467 (1987); Schieffelin & Co. v. Department of Liquor Control, 194 Conn. 165, 186, 479 A.2d 1191 (1984); Brunswick Corporation v. Liquor Control Commission, 184 Conn. 75, 82-83, 440 A.2d 792 (1981). The plaintiffs have not satisfied this heavy burden. It was not arbitrary or irrational for the legislature to decide that its goal of enhancing the quality of the state’s educational system as a whole required even teachers who had attained permanent status to continue to sharpen their educational skills. We thus conclude that the act does not violate the plaintiffs’ rights to substantive due process.
II
Finally, the plaintiffs argue that the act violates the constitutional prohibition against impairment of the obligation of their contracts with their respective employers, the local and regional boards of education. U.S. Const., art. I, § 10.13 Their claim of impairment has three predicates, not all of which are equally persuasive. First, General Statutes (Rev. to 1989) § 10-151 (c) and (d)14 creates a continuing obligation on [301]*301the part of each board of education to employ the plaintiffs while they are properly certified.15 Second, General Statutes (Rev. to 1989) § 10-145 precludes a board of education from continuing to employ or pay a teacher who does not possess a state-issued certificate. Third, any substantial impairment of their continued access to state-issued certification interferes with their employment relationships with their boards of education. We have no reason to question the first two of these predicates. With respect to the third, however, we conclude that the plaintiffs’ employment contracts have not been unconstitutionally impaired by making their teaching certificates, and hence their continued employability, conditional upon their completion of nine CEUs every five teaching years, as required by General Statutes (Rev. to 1989) § 10-145b (i).
“Unlike other provisions in [article I], it is well-settled that the prohibition against impairing the obligation of contracts is not to be read literally.” Keystone Bituminous Coal Assn. v. DeBenedictis, 480 U.S. 470, 502, 107 S. Ct. 1232, 94 L. Ed. 2d 472 (1987); see also Home Building & Loan Assn. v. Blaisdell, 290 U.S. 398, 428, 54 S. Ct. 231, 78 L. Ed. 413 (1934). “Thus, a finding that there has been a technical impairment is merely a preliminary step in resolving the more difficult question whether that impairment is permitted under the [302]*302Constitution.” United States Trust Co. v. New Jersey, 431 U.S. 1, 21, 97 S. Ct. 1505, 52 L. Ed. 2d 92, reh. denied, 431 U.S. 975, 97 S. Ct. 2942, 53 L. Ed. 2d 1073 (1977). “The threshold question is whether the state law has in fact operated as a substantial impairment of a contractual relationship. Energy Reserves Group, Inc. v. Kansas Power & Light Co., 459 U.S. 400, 103 S. Ct. 697, 74 L. Ed. 2d 569 (1983). Factors to be weighed are the severity of the impairment, the extent to which it frustrates a party’s reasonable contractual expectations and the extent to which the subject matter of the impairment has been regulated in the past. Id. If the impairment is minimal the inquiry may end at the embryonic stage. Allied Structural Steel Co. v. Spannaus, 438 U.S. 234, 245, 98 S. Ct. 2716, 57 L. Ed. 2d 727, reh. denied, 439 U.S. 886, 99 S. Ct. 233, 58 L. Ed. 2d 201 (1978). If, however, the impairment is severe, the legislation will be subjected to an increased level of scrutiny.” Schieffelin & Co. v. Department of Liquor Control, supra, 177-78.
Viewed from this perspective, the plaintiffs’ claim of impairment of contract obligation is, in the present context, virtually indistinguishable from their substantive due process claims, which we have already rejected in part IB of this opinion. The changes wrought by General Statutes (Rev. to 1989) § 10-145b (i) do not constitute a constitutionally unacceptable impairment of the plaintiffs’ teaching contracts. We are hard put to characterize that impairment as anything other than minimal. Furthermore, “[ejven a substantial impairment of a contractual relationship may be justified if the state regulation has a significant and legitimate purpose. Energy Reserves Group, Inc. v. Kansas Power & Light Co., supra, 403; United States Trust Co. v. New Jersey, supra, 22.” Schieffelin & Co. v. Department of Liquor Control, supra, 182. As we have noted above, the act has the significant, legitimate purpose of upgrading the [303]*303state’s public education system. Thus, even if we were to conclude that the act significantly impairs the plaintiffs’ contractual relationships, the state has a sufficient interest in exercising its police power in this area for the act to pass constitutional muster.
The plaintiffs finally claim that the state was constitutionally obligated to pursue legislative alternatives that would have avoided “the draconian impact of invalidating ‘permanent’ certificates.” They argue that the General Assembly could have encouraged teachers to undertake continuing education voluntarily, by financial incentives, by restricting funds to those who do not apply for professional educator certificates or by a “myriad” of other devices. We recognize that “a State is not free to impose a drastic impairment when an evident and more moderate course would serve its purpose equally well.” United States Trust Co. v. New Jersey, supra, 31. We do not, however, agree that the means chosen by the legislature were so “drastic” or the suggested alternatives so likely to succeed that the legislature’s course of action constituted an unconstitutional impairment of the plaintiffs’ contracts of employment.
The question reserved to this court was: “Whether [General Statutes (Rev. to 1989) § 10-145b (i)J as it applies to holders of standard or permanent certificates is unconstitutional under Article First, Section 8, amended by Article XVII of the Connecticut Constitution, and/or Article First, Section 10 of the United States Constitution, and/or the Fifth Amendment of the United States Constitution and/or the Fourteenth Amendment to the United States Constitution.” For the reasons stated above, we answer “No” to the reserved question.
No costs will be taxed in this court to either party.
In this opinion the other justices concurred.