Guidelines, care pathways, and other representations of high quality clinical practice can now be formalized and distributed in executable form. It is widely recognized that the ability to apply knowledge at the point of care creates an opportunity to influence clinicians’ behavior, encouraging compliance with evidence-based standards and improving care quality. The ability to share formal knowledge may also enable the medical community to build on work done by others and reduce content development costs. We propose a Medical Knowledge Repository and content model that supports assembly of components into new applications. Some types of resources that may be included in such a repository are defined, and a frame-based representation for indexing and structuring the components is described. The domain of breast cancer is used as a case study for demonstrating the feasibility of the approach.