Health promotion is inherently political. Not only is it largely funded by government, but the very nature of the enterprise requires shifts in power. Political theory has much to contribute to an understanding of the politics of health promotion. In this paper three key political theories are explained and their insights for health promotion explored. They are then applied to the development of a National Drug Policy in New Zealand. The theories—pluralist interest group theory, the new institutionalism and neo-Marxist theory—are each at a different level of analysis. The significance of interests, institutional factors and class as political influences on health promotion are discussed. It is concluded that to ensure good practice health promotion practitioners need to be aware of these influences on their work. They need to strategise to ensure support from key interests, build capacity for health promotion into their institutions and recognise the macro-political context within which they work in order to influence it.