Objective. Little information is available about the effectiveness of school entry vaccination requirements at the middle school level. This study examined coverage levels among students entering seventh grade in Florida following implementation of a school entry vaccination requirement in 1997. Methods. The authors analyzed county-specific vaccination coverage levels (three doses of hepatitis B vaccine, a second dose of measles, mumps, and rubella [MMR] vaccine, and a booster dose of tetanus and diphtheria toxoids [Td]) among students entering public and private schools in Florida from 1997 through 2000. In 1998, a survey of all county health departments was con-ducted, and the resulting data were linked to county-specific vaccination rate...