The Global Entrepreneurship Monitor’s (GEM) social entrepreneurship activity research is based on interviews with approximately 150,000 adults in 49 countries during 2009. Special questions were added to the GEM 2009 Adult Population Survey (APS) to document the prevalence of social entrepreneurship. GEM defines social entrepreneurship broadly, however, based on a number of follow-up questions with individuals in the population screened out as social entrepreneurs in the 2009 APS. Deeper analysis led to the development of subcategories of social entrepreneurship. Given the scarcity of data on social entrepreneurship activity around the world and the many existing definitions of social entrepreneurship, this report produces unique insights, as it represents the first global and harmonized assessment of social entrepreneurship activity.