In the U.K., a current government health strategy indicates that school nurses should be key contributors to sexual health education because they have access to the school-age population. However, there appears to be little research that investigates whether school nurses are the most appropriate health care professionals or indeed have sufficient knowledge to contribute to this topic in the schools. The purpose of this study was to examine the sexual health knowledge of school nurses, using a survey to assess school nurses employed in a large central region of the U.K. The results suggest that although their general knowledge of the topic was adequate, school nurses have insufficient knowledge to effectively teach about sexually transmitted infections or emergency contraception. This has implications for school nursing because it appears that school nurses may have inadequate knowledge about sexual health to contribute to sex education in schools. (Contains 1 table and 2 figures.)