In politics, a regime (also "régime") is the form of government or the set of rules, cultural or social norms, etc. that regulate the operation of a government or institution and its interactions with society. The two broad categories of regimes that appear in most literature are democratic and autocratic. However, autocratic regimes can be broken down into a subset of many different types (dictatorial, totalitarian, absolutist, monarchic, oligarchic, etc.). The key similarity between all regimes are the presence of rulers, and either formal or informal institutions.

According to Yale professor Juan José Linz there a three main types of political regimes today: democracies, totalitarian regimes and, sitting between these two, authoritarian regimes (with hybrid regimes).