Segregation on racial grounds in education, employment, housing, before the law or in public services, may be a matter of government policy (South Africa) or of custom and general practice. Racial segregation preserves racial conflict, prejudices and discrimination, lack of integration, lack of social mobility, and inequalities.
Segregation usually is a means of maintaining the economic advantages and the superior social status of the politically dominant racial group. In an urban industrial society it is difficult to maintain the physical segregation of races, and more dependence must be placed upon institutions to maintain it. Consequently, the races live in different social worlds and communication between them is restricted, regardless of physical proximity. As an ecological process, racial segregation is in a way a natural one since it results from a relatively impersonal competition between races for space or land. As far as the economic relations of races are determined only by competition, a racial division of labour may emerge, which results in the 'segregation' of racial groups in different occupations. The racial division of labour generally reflects the distribution of power in a community. Thus, the system of Negro slavery and the economic organization of life in the Southern USA as well as in the colonial areas in Africa represented a racial division of labour but with a clear relation between that division and the distribution of power.
The phenomenon of racial segregation has appeared in all parts of the world where there are bi-racial communities, except where racial amalgamation has occurred on a large scale, as in Hawaii and Brazil. The problem of racial segregation is most acute in South Africa.