A system of government or administration. The most common use of this promiscuous term in recent years has been in the phrase ‘military regime’. So while any government may be termed a regime, be it monarchical, aristocratic, republican, or tyrannical, the term unavoidably conjures up memories of tanks in the streets in Latin American capitals. This is to be regretted, since it has two more technical senses in which it may not easily be replaced. First, when governments come and go with bewildering frequency, as in nineteenth‐century Spain or post‐1945 Italy, there may still be an absence of fundamental or revolutionary change. In these circumstances it is possible to speak of regime continuity. Alternatively, and more rarely, a change of regime (from constitutional monarchy to tyranny, or from dispersed to centralized government) may be achieved without a change in government, as in the move from parliamentary to personal rule by Charles I of England, or in Britain under Margaret Thatcher. Secondly, in international relations the difficulty of accommodating the rise of non‐state actors and complex interdependence within state‐centric realist models of explanation has led to use of the term ‘regime’ to cover norm‐bound interactions relating to issues such as the global environment or human rights, in which states, international organizations, transnational corporations, individuals, and worldwide pressure groups like Greenpeace or Amnesty International all take part.