The pilot studies used samples of 48 and 45 children from two schools. Each sample had equal numbers of children ages 6, 8, and 10 years. The main study used 168 children from four additional schools. The children individually viewed a series of videotaped scenarios in which a child was approached by a man with whom the child was familiar or unfamiliar and who made a request or an offer or a demand. The viewing children were asked what they thought the child in the video would do and why they would do it. Results indicated that, although children appear to develop increasing wariness as they become older, children at ages 8 and even 10 years appear still to be vulnerable to approaches made by strangers. Findings suggest that, to learn to keep themselves safe, children must have the opportunity to explore, through discussion and role play, a wide variety of safety situations and their potential risks and resolutions. It is also necessary for safety messages to be repeated to children throughout their school careers and to try to establish the individual vulnerabilities of children. Tables, figures, and 12 references