This article presents a dynamic theory of parliamentary governments that incorporates attributes of the institutional system in a country, exogenous events that shape parliamentary and electoral opportunities, and the strategies of the government and the opposition as structured by institutions and preferences. The dynamics are investigated in an infinitely repeated game in which events in the form of shocks to income or government resources occur and the government responds with a legislative proposal that is subject to a confidence or censure procedure and may lead to government continuation, reorganization, or dissolution. With a majority confidence procedure, governments are stable, and if parties are politically patient, voting cohesion within the government is high. A censure motion initiated by the opposition can result in voluntary dissolution of government, and the approach of required elections increases the likelihood of dissolution. If the events represent fluctuations in aggregate income, governnment dissolution occurs in good times for the government leader and bad times for the other parties.