Translation theory originates in the field of applied linguistics and communication. The term knowledge translation has been adopted in health and other fields to refer to the exchange, synthesis, and application of knowledge. The logic model is a circular or iterative loop among various knowledge translation actors (knowledge producers and users) with translation activities evolving and occurring at various stages. Successful knowledge translation depends on the engagement of the target audience, as well as using the knowledge to inform decisions and have a positive influence on health outcomes. Understanding this alerts the evaluator to how to maximize the likely usefulness and sustainability of their evaluation research with local stakeholders. It also invites evaluators to help appreciate why programs have the short- and long-term effects that they have, particularly any unintended or unexpected program outcomes that might have otherwise been puzzling. © Wiley Periodicals, Inc., and the American Evaluation Association.