Integrated care pathways, a fine-grained form of medical guideline including the explicit recording of any deviation, or ‘variance’, have been perceived by some as overly prescriptive, limiting clinical freedom and promoting ‘cookbook medicine’. However, feeding the results of the analysis of variance back into the development of a pathway could be an effective way of capturing evidence from practice. This paper summarizes research into the development and use of ICPs, and includes some initial findings from a qualitative study involving clinicians that have helped develop or have used ICPs professionally.