This chapter discusses that the quality of social relations is better in more equal societies where income differences between rich and poor are smaller. It describes that in these more equal societies, people are much more likely to trust each other, measures of social capital and social cohesion show that community life is stronger, and homicide rates and levels of violence are consistently lower. Psychological literature, concentrating as it does on the individual, too often ignores the susceptibility to the powerful sociological processes that drive social differentiation and discrimination against those lower down the social hierarchy. The sociological literature that addresses issues of social class stratification usually ignores its interaction with individual psychology. The strongest evidence that the quality of social relations is related to income inequality comes from studies of violent crime and homicide. Legal definitions and published statistics on many different kinds of crime usually differ too much from country to country to allow sound international comparisons.