Few studies have considered families' views about adolescents' sexual development. The authors compared attitudes and behaviors of mothers of young people with (n = 30) and without intellectual disability (n = 30). Both groups placed similar importance on dealing with their children's developing sexuality and were similarly confident in doing so. Mothers of young people with intellectual disability held more cautious attitudes about contraception, readiness to learn about sex, and decisions about intimate relationships. Mothers expressed concerns about their children with intellectual disability and sexual vulnerability. They had also spoken about fewer sexual topics with their children and began these discussions when their children were older. The findings can inform more sensitive supports and materials to help families deal with the sexual development of their offspring.