There are many reports on how Information Systems Development (ISD) methods are adapted before they are used. The need to customise methods is explained by the variety of systems that are developed and the various situations in which information systems can be developed. This means that the development process knowledge embedded in an ISD method can be used in different ways in different situations. The study presented in this paper is a follow up of a study of how a widespread ISD method was adapted and introduced in an organisation. In this paper we focus on how the development method was actually used in a project. The paper extends an earlier model of analysis for characterising information systems development in terms of knowledge work. The model recognises four classes of knowledge work: routine, craft-like, professional, and creative knowledge work. We use that particular model to elaborate on how the various kinds of knowledge work presented interact in an actual development situation. The main contributions of the paper are the application of the analysis model on an empirical case and the extension of the analysis model to comprise the interactions between the different types of knowledge work.