Classic liberalism is a political school of thought that holds that all rights are held by individuals, and that governments are put into place solely in order to defend those rights. Classic liberals promote the use of restrictive constitutions in the formation of governments, to ensure that their role is constrained to the defense of these rights.

The classic liberal philosophy places a particular emphasis on the role of property rights in ensuring the rights of the individual, and forms the philosophical underpinning of the free market system.

The precepts of classic liberalism were probably best described by John Locke and Adam Smith, and illuminated much of the thought at the time of the American revolution. As a result, the United States Constitution and the United States Declaration of Independence are both documents that embody many principles of classic liberalism.

Modern liberalism tends to deviate from this definition of the term "liberal" in that it espouses the use of the power of government to achieve a variety of desirable goals, ranging from social justice to economic equality.

The libertarian movement is probably the closest modern derivative of classic liberalism, although other political movements and parties sometimes incorporate its ideals, and often borrow from its rhetoric.