Agile information systems development (ISD) is a people-centered approach that emphasizes frequent interaction and genuine co-operation between customers and developers. While business relationships are the norm in the workplace, agile ISD leads to the creation of close interpersonal relationships. Drawing on relationship theory and friendship literature we propose a theoretical framework of three types of workplace relationships. The framework is used for deriving theoretical preconceptions about agile relationships and their impact on the agile ISD team’s ability to deliver valuable, working software frequently. We also present the interpretive approach we will apply. An understanding of the relationship specific aspects of agile ISD as well as of the importance and impact of certain relationship characteristics can help explain why some agile projects succeed, while others fail. Such knowledge can also be used to foster friends-like behavior for the benefit of the software outcome in future projects.