This article explores the areas of British politics that rational choice could examine. Constitutional law, descriptive analyses, and the relative power of the prime minister once dominated core executive studies. Continuing reforms of core executive organization provide an ideal subject for study. Political economy models have been applied rather simply to the civil service using a selected and rather dated band of models. The British parliament offers less scope for strategic analysis than stronger less coherent legislatures. There are areas where rational choice has provided great insights, historically to key features of the British state, to local government and local–central relations, in voting studies, the core executive, and more recently new sets of ideas applied to cabinet studies and the relationship between parliament and the executive. Rational choice theory is not a dominant mode of analysis in Britain, but there is much that can be usefully studied through the rational choice lens.