This does not preclude altruistic motives or enlightened leadership by policy makers. It is recognised that individuals care about the well-being of their fellow citizens and the environment, and that politicians derive satisfaction from pursuing socially beneficial policies. The self interest assumption therefore captures the concept that behaviour is governed by attempts to maximise well-defined objectives, which may include both altruistic and egoistic motives. Governments are likely to be motivated by a number of factors such as ideological objectives, social welfare, the pursuit of economic efficiency, and the desire to retain office, and government policy decisions will reflect these complex objectives.