Current economic conditions have increased pressure on foundations to optimize their investments. This article offers a tool for doing this in an area of high leverage: leadership development. It offers a framework for assessing a foundation’s current approach in this area that reflects the rising significance of collective leadership. This article is based on an in-depth review of leadership development practices carried out by one of the authors in three sectors – government, business, and social – as well as in the emerging multistakeholder sector. It reflects as well another of the authors’ experiences evaluating leadership development programs and initiatives that have vastly different purposes, and co-creating with funders and evaluators a framework for assessing leadership investments that can guide program and evaluation design.