Health information exchange (HIE) projects are sweeping the nation, with hopes that they will lead to high quality, efficient care, yet the literature on their measured benefits remains sparse. To the degree that the field adopts a common set of evaluation strategies, duplicate work can be reduced and meta-analysis will be easier. The United Hospital Fund sponsored a meeting to address HIE evaluation. HIE projects are diverse with many kinds of effects. Assessment of the operation of the HIE infrastructure and of usage should be done for all projects. The immediate business case must be demonstrated for the stakeholders. Rigorous evaluation of the effect on quality may only need to be done for a handful of projects, with simpler process studies elsewhere. Unintended consequences should be monitored. A comprehensive study of return on investment requires an assessment of all effects. Program evaluation across several projects may help set future policy.