The 1,350 3- to 6-year-old children who participated in the study included 1,044 experimental subjects and 295 controls, all of whom attended day-care centers in the metropolitan Baltimore area and were taught a prevention curriculum by their day-care teachers. All teachers had participated in an 18-hour training program designed to help them identify sexual abuse and to deliver the Children's Primary Prevention Training Program, specifically designed for these age groups. The What If Situation Test (WIST) was administered as a pretest and a posttest, six weeks after completion of the program. The results showed that all children who participated in the program demonstrated greater knowledge of personal safety rules and skills compared to controls. However, the 6-year-old children performed significantly better than the 3- and 4-year-old children. 1 figure, 1 table, and 44 references