To assure a future for endangered primates and many other species, we must develop and carry out projects for their conservation as quickly and effectively as possible, even with only limited information about the complex systems of biological, political, social, economic, and cultural factors influencing the conservation situation. Adaptive management, defined as the integration of design, management, and monitoring to systematically test assumptions to learn and adapt, provides practitioners a method for improving strategies to achieve and sustain the desired conservation impact. The Conservation Measures Partnership, a joint venture of conservation NGOs, developed the Open Standards for the Practice of Conservation, a freely available framework that guides practitioners through implementation of best conservation practices. Using this process, project teams are explicit about the assumptions behind the strategies they choose, and thus able to trace their successes and failures back to good or poor theory, implementation, or a combination of the two. The Open Standards comprise five steps that constitute the project management cycle: (1) Conceptualize what you will achieve in the context of where you are working—involves defining your project team, scope, vision, conservation targets, critical threats, and analyzing the situation; (2) Plan your actions and monitoring—involves developing an action plan including goals, strategies, assumptions, objectives, and activities; a monitoring plan including indicators for measuring the status of goals, objectives, and assumptions; and an operational plan specifying the resources needed; (3) Implement your actions and monitoring—includes developing and implementing detailed work plans and ensuring sufficient resources, capacity, and partners; (4) Analyze, use, and adapt—involves managing monitoring data, regular analysis to convert them to useful information, and adapting the project plans accordingly; and (5) Capture and share learning—involves sharing lessons with key external and internal audiences to promote a learning culture. Am. J. Primatol. 72:425–440, 2010. © 2010 Wiley-Liss, Inc.