Social and economic variables in Japan account for differences in the frequency and type of child abuse cases. The murder of infants as a form of population control became a serious social problem in Japan by 1975 when the term coin- operated locker baby was introduced. These infants were primarily neonates and predominantly male babies. Parents or assailants were difficult to locate, most infants appeared to have died of asphyxiation, and they were discovered 1 to 3 months after death and were usually wrapped in plastic. In 1981, the number of coin- operated locker babies began to decrease in response to certain actions. Coin-operated lockers were relocated to make them more visible, and patrols were assigned to monitor locker areas. In addition, the problem of coin-operated locker babies was publicized and became recognized by the general population. Education about contraception also decreased the number of unwanted babies. More recently, the government of Osaka organized a group specifically designed to focus on the detection and protection of abused and neglected children. In 1993, this group published a manual on how to deal with child abuse. Even so, the Japanese judicial system still uses old laws for child abuse cases, although new laws are emerging in parts of the country. As social conditions in Japan change, the reported incidence of child abuse may increase if social welfare priorities and budgets are not revised to prevent, detect, and treat child abuse. 14 references, 2 tables, and 2 figures