Substantive law is the set of laws that governs how members of a society are to behave. It is contrasted with procedural law, which is the set of procedures for making, administering, and enforcing substantive law. Substantive law defines rights and responsibilities in civil law, and crimes and punishments in criminal law. It may be codified in statutes or exist through precedent in common law.
Henry Sumner Maine said of early law, "So great is the ascendency of the Law of Actions in the infancy of Courts of Justice, that substantive law has at first the look of being gradually secreted in the interstices of procedure; and the early lawyer can only see the law through the envelope of its technical forms."