People with intellectual disabilities face challenges in the area of sexuality that might differ from challenges their non-disabled peers face. For example, people with intellectual disabilities tend to be less informed about sexuality, have fewer sexual experiences, have more negative attitudes towards sexual activities and have more experiences with sexual abuse, than those without intellectual disabilities. Additionally, people with intellectual disabilities express problems in finding, forming and maintaining (sexual) relationships. These problems greatly influence the sexual health and consequently the quality of life of people with intellectual disabilities.

Many of these problems are influenced by environmental factors, such as parents or paid care staff. For example, people with intellectual disabilities receive less sex education, which could explain their low levels of sexual knowledge and their inability to protect themselves against sexual abuse. Furthermore, people with intellectual disabilities experience restrictive rules and a lack of privacy regarding sexual expressions, which could explain their lack of sexual opportunities. Sex education could be used as a tool to improve some of these problems, both on the individual and environmental level, and consequently improve the sexual health of people with intellectual disabilities. The first study, described in chapter 2, was conducted to identify existing sex education programs geared towards people with intellectual disabilities in the Netherlands. This was an important first step to take before considering the development of new sex education materials. The goal of this study was to utilize what is learned from these programs in future development of sex education materials. The program developers of five existing sex education programs were interviewed, using Intervention Mapping as a guideline. Results revealed that the programs were not evaluated; lacked a theoretical basis; did not involve members of relevant populations (eg people with intellectual disabilities, paid care staff) in the program development; and lacked specific program goals. In conclusion, future sex education programs geared towards people with intellectual disabilities should be developed using a more systematic and theory-and evidence-based approach, such as Intervention Mapping, to increase the likelihood that the program will be effective in improving the sexual health of people with intellectual disabilities. Chapter 3 describes a cross-sectional survey conducted among 163 paid care staff members. This study was conducted, because in the first study program developers indicated staff members to be an important population for teaching sex education to people with intellectual disabilities. It was therefore essential to investigate whether they are indeed an ideal population to teach sex education by identifying the factors that influence whether staff members teach sex education to their clients or not. The results show that 39% of the staff members teach sex education and most likely do this reactively. This is opposite to what most sex educa-