While integrated care programs are proliferating around the world, rigorous measurement and evaluation of the intended and unintended effects of these programs are rare outside of the context of specific research programs. There are a number of reasons for the lack of evaluation including implementation without regard to measurement and evaluation, a lack of funding for evaluation activity, and challenges associated with measurement and evaluation in complex interventions. As a result, most research on integrated care is descriptive including case studies that most often summarize what was implemented, in some cases how it was implemented, but far less often what outcomes were achieved.