The interest function approach to government behaviour, initiated by van Winden [1983], is used to investigate how demand for local public services differs among population groups and how the groups’ political influence is shaped by numerical strength and the party composition of the local council. W e improve upon earlier empirical applications of the interest function approach by clarifying the condition under which both taste and influence parameters can be identified. Moreover, the model is estimated in a situation in which the condition for identification is met.