A household sample, stratified by catchment area, was selected using a two-stage probability technique. A total of 3,132 adults (18 years or older) were interviewed between January 1983 and August 1984. The sample was 46 percent Hispanic and 42 percent non-Hispanic whites. 47 percent male and 53 percent female. Childhood sexual assault was defined as incidents before age 16 years which involved pressure or force for sexual contact. The prevalence (weighted for sampling design and nonresponse) of childhood sexual assault for the total sample was 5.3 percent. Rates were higher for non-Hispanic whites (8.7 percent) compared with Hispanics (3.0 percent), women (6.8 percent) compared with men (3.8 percent), and younger persons at the time of interview 6.5 percent compared with older persons (3.9 percent). Most assaults were by an acquaintance and occurred for the first time around age 10 years. Data from a subsample of assaulted respondents show that childhood sexual assaults are not usually accomplished through physical aggression, but rather through persuasion, and through the psychological threat of the assailant being bigger or stronger. Research is needed on the natural history and sequelae of childhood sexual assault. Tabular data. 18 references. (Author abstract)