The Civil Society Organization Sustainability Index (CSOSI) has been used since 1997 to assess the sustainability of the CSO sector. The Index has expanded considerably since its inception – it went from covering 18 countries in the Europe and Eurasia Region, to covering over 60 countries in different regions around the world. By using standard indicators and collecting data each year, the CSOSI enables users to track developments and identify trends in the CSO sector over time while allowing for cross-country and cross-region comparison. It is used by CSO advocates, development partners, and academics to assess international and regional trends in the civil society sector and to identify common obstacles impeding the sector’s sustainability, such as the legal environment, organizational capacity, and financial viability. This is the first time Sri Lanka is participating in the index. Verité Research is the local implementing partner for the CSOSI.