Historically, examples of project evaluation in conservation were rare. In recent years, however, conservation professionals have begun to recognize the importance of evaluation both for accountability and for improving project interventions. Even with this growing interest in evaluation, the conservation community has paid little attention to evaluation design. Recent literature includes some discussion of design, but it has focused primarily on experimental and quasi-experimental design and the use of counterfactuals. Real-life conservation projects, however, operate in complex and dynamic contexts and under conditions of limited resources, which limit the feasibility of counterfactual or experimental designs. There is, in fact, a range of design options to evaluate conservation interventions. The conservation community must educate itself about these options, and how different designs produce different results. This chapter discusses evaluation design alternatives in light of the unique challenges that influence evaluation design selection in conservation. © Wiley Periodicals, Inc.