The purpose of this paper is to outline a social action perspective of information systems development (ISD) and provide some evidence for its fruitfulness. Earlier theories have looked upon ISD as a technical engineering process or as a technical process with behavioral consequences. These theories have not proved adequate for understanding the systems development process. The social action perspective as advocated in this paper leads one to realize that ISD is a social process which relies on technology. The paper introduces the following basic building blocks of the social action perspective for ISD. human interests, objective and subjective knowledge and meanings, power, conflict, resistance, and consensus formation. It is shown how these social action concepts contribute to our understanding of the systems development process. Evidence for this is presented from case studies. It is concluded that any theory of ISD which does not explicitly deal with the key phenomena of social action is inadequate. In practice, ISD is politics first, engineering second.