This paper discusses the differences between a positivist research philosophy and one which is increasingly emerging in IS research - an interpretive research philosophy, as they relate to case research, by examining selected case studies drawn from recent published IS case research. Each perspective places a different emphasis on case research, reflecting different ways of viewing reality and the pursuit of valid knowledge. This is an important realisation that can help us understand the debate that often arises over the nature and stature of case studies as a method for conducting research.