Contract Law General Theory of Contracts The General Theory of Contracts is an umbrella term used in civil law jurisdictions, like Spain and Latin America, that refers to the body of law that governs contracts. In the U.S. and other common law jurisdictions, the equivalent would simply be Contract Law or Law of Contracts. They both concern principles and rules that regulate agreements made between parties, detailing how contracts are formed, executed, and potentially breached, and what remedies are available.