This document discusses sources of crime data and different theories of criminology. It describes the Uniform Crime Reports and National Incident Based Reporting System as two major sources of crime data in the US. It also summarizes biological, psychological, sociological, and conflict theories of criminology. Biological theories view crime as influenced by genetic and physiological factors while psychological theories examine individual mental processes and conditioning. Sociological theories analyze group dynamics and social disorganization. Conflict theories see crime as resulting from economic and social inequalities between groups in society. The document outlines the key assumptions and social policy implications of each theoretical perspective.