A number of model repositories are identified in the literature. Many of these models support computational biology applications, and certainly, by some measures are more sophisticated than the MREP we describe here. One manifestation of sophistication is using a markup language based on XML concepts that imposes a standard method for describing and representing models common to a repository. We assert that ABMs are conceptually less mature than computational biology models, and broader in their scope (i.e., agents can represent genes, proteins, and cis-regulatory elements at one end of the spectrum, and represent people, states, and countries at the other end). We chose not to grapple with the notion of trying to develop a common taxonomy to describe agent-based epidemiology models. Rather, we focused on building a repository that captures ABMs in whatever form they were developed and creates a common set of documentation and annotations, so that the model can be understood (at some level) and reused should the need arise.