This paper first provides an overview of the existing conceptual frameworks and international standards related to building statistics about the social and solidarity economy (SSE). It then looks at how the perimeter for SSE is set in the cases of the two main frameworks presently at hand: the “social economy approach,” as embodied in the CIRIEC Manual on drawing up satellite accounts and in the ILO Guidelines concerning statistics on coopera-tives, and the “NPO approach”, as embodied in the United Nations NPI and TSE handbooks on non-profit and related institutions. The third section of the paper discusses how constructing statistics about SSE typically entails identifying sources, such as registers, surveys and censuses, that will serve as the basis for the statistical construction of the SSE population. The next two sections explore how the SSE organizations thus selected are then classified, based on criteria such as the sector of activity and the type of organization, and how the information that relates to them is collected, based on methodologies such as satellite accounts or observatories. Section six then shows how indicators related to employment, membership and economic contribution could complement this work of measurement. The paper concludes with an assessment of the strengths and weaknesses of each approach, as well as recommendations for future work.