The purpose of this paper is to argue that research and practice of ISD could substantially benefit from interpreting ISD as knowledge work. Two distinct areas of competence are identified for system developers: IS application knowledge and ISD process knowledge. Focusing on process knowledge, the authors propose a template for organizing the body of process knowledge in ISD consisting of four levels: systems development techniques, methods, approaches and paradigms. The conclusions discuss implications of the knowledge work perspective for the education of IS experts