The concept and term social economy is very broad, but it is generally understood to refer to all types of economic and social activities that take place in many legal forms between the boundaries of the private and public sector. Social economy is a term that is commonly used in continental Europe, and in the European Union institutions. Furthermore, as the theoretical and the research areas covering the social economy/third sector are vast, complex and full of different interpretations, particularly on its various sub-components, it is beyond the limits of this paper to deal with these in detail. The article introduces a series of basic notions for understanding how the European Union approaches the General Objective of Social and Economical Cohesion.