This paper presents the analytical properties of Social Accounting Analyses methods, especially models based on simple and extended Social Accounting Matrices (SAM) and their application to the investigation of spatial economic interactions and flows patterns, including those associated with the spatial employment impacts of the CAP. Section 2 presents the structure, assumptions and characteristics of interregional SAMs and deals with their modeling properties, which make possible the investigation of spatial economic interactions. Section 3 presents recent developments in SAM construction and model applications relevant to the analysis of such issues, including that of CAP employment impacts. Finally, the Chapter concludes with a short critical evaluation of advantages and shortcomings of the SAM approach to analyze and interpret the determinants of the spatial distribution of economic activity and suggests future research directions.