The dissertation addresses a call to investigate the puzzle if not all NPOs are innovative, then which factors make some NPOs more likely to produce social innovations than others? The dissertation investigates the determinants of social innovativeness of non-profits and elaborates scales to identify socially innovative NPOs while quantitative survey. The dissertation, first, investigates what is social innovation, how it refers to non-profits, and reveals what elements constitute social innovation and distinguish it from other types of innovations. Secondly, this dissertation discusses the methodological shortcomings of existing metrics of social innovations and develop quantitative scales to identify the socially innovative non-profit organization. The empirical basis of this dissertation is a survey of non-profits in Russia (n=850, 2015). Despite the majority of the existing qualitative metrics, the proposed scales could be administered simultaneously and provide empirical data on the scope and size of a sub-sector of socially innovative NGOs