In this paper an attempt is made to present a comprehensive picture of the effects of separation and divorce on children. After information on trends in divorce is presented to indicate how many families and children are involved, three comprehensive reviews of one-parent families are discussed. Because some detrimental effects are associated with father absence, literature focused on family relationships and conditions of family life is reviewed to locate possible explanations for these effects. Topics explored include reasons for father absence, family conflict, parent/child relationships, financial resources of parents, and social supports. Factors accounting for the discrepancy between ability and school performance among children from one-parent families are suggested in a brief review of selected, recent studies. In conclusion, research needs in several areas related to children in one-parent families are pointed out. (Author/RH)