The author argues that many foundations have substituted process accountability for accountability for contributing to social change. Accountability in terms of required reporting is important, but it sets a floor, not an aspirational ceiling. Seeking to extend basic human rights to more individuals around the world, seeking to reduce racism in a given city, or seeking to change public-health norms in small town-all of these aspirations require first a willingness to take on challenges that defy short-term, causal, quantifiable results attributable to a best practice. There are tools-such as risk analysis, systems approaches, and game theory-that can help philanthropy engage in work on complex social problems that cannot be deconstructed into a series of small, linear projects. © 2010 The Foundation Review.