This paper reports sex education preferences from an ethnically diverse sample of 3007 15-18 year olds. Findings are presented on preferred topics, where and from whom young people would like to receive this information. Preferences were centred around learning more about sexual behaviour and sexually transmitted infections (STIs) in particular, and receiving this at school from someone "professional" and of similar age. Females showed a greater preference towards learning about emotions, relationships and contraception, and to having this delivered by someone of the same sex. Of the four main ethnic groups, Black and Asian students generally reported more sex education preferences than White British or White Other students. Black students wanted to learn more about biological issues and cultural issues alongside sexual behaviour and STIs. Black male students reported a greater than average preference towards family-based information, and interest towards someone of the same ethnic background delivering sex education was also expressed. Asian students reported stronger preferences for more information about STIs and contraception, and wished to keep sex education out of the family household. Implications for sex and relationships education and working with professionals and parents are outlined. (Contains 3 tables.)