This paper reports the results of the first academic study of the use of a major social networking website, MySpace, by children. The study examined the degree of, and reasons for, information disclosure by children in high schools in Sydney, Australia. Social networking sites such as MySpace are a huge Internet phenomenon, some with hundreds of millions of users and often the most visited Internet sites on a daily basis. They are particularly attractive to, and used by, children, perhaps eclipsing email as a preferred communications medium. This study shows that, by and large, children are acting responsibly in embracing this new technology, however, there are a significant number potentially at risk, possibly due to their lacking individual personal privacy values. The paper concludes with a call for parents and teachers to become more familiar with social networking and to help their charges understand the implications of its use. (Contains 5 tables and 7 figures.)