A nationally representative sample of 5,000 families will be interviewed to: (1) Obtain current data on the incidence of intra-family physical violence, including child abuse, spouse abuse, parent abuse, and sibling abuse. (2) Estimate changes in the incidence of family violence in the ten years between 1975 and 1984-85. The findings from objectives 1 and 2 will be useful for criminal justice, mental health, and other human service agencies, which need current data as a basis for policy formulation and service planning. The data on change in family violence rates can be used as a frame of reference for evaluating the policies and programs of the past ten years, and is also an important indicator of the "quality of life" in American families. (3) Obtain incidence rate data and conduct analyses focused on certain groups which were not included in the 1976 study, or for which the sample was not large enough to study with the 1976 data: children under 3, single parent families, and the previous marriages of recently divorced persons. There are grounds for thinking that each of these represent particularly high risk of violence situations. The findings can have important implications for prevention and treatment work. (4) Improve the Conflict Tactics Scale. This is a widely used instrument in the field and its further development will aid the mental health research community. (5) Replicate and extend some of the previous analyses of factors which might contribute to the occurrence of family violence. The findings of that study are widely used as one of the bases for current policy and service provisions. Consequently, it is important to test the reliability of the findings. (6) Investigate issues which, because of limitations of the 1976 study, could not be adequately investigated with that data. This will include testing certain aspects of exchange theory and control theory. These theories, if supported, have implications for the prevention and control of family violence. (7) Obtain information on the immediate and long term consequences of family violence, including physical injury, use of criminal justice and social services, and mental health problems. Rough estimates will also be made of the monetary cost to society of violence between spouses. These findings will provide mental health and criminal justice agencies with information on the adequacy of programs in meeting the needs of abuse victims; and where problems are discovered, will suggest ways of improving those services.