Background: Attitudes to the sexual expression of adults with an intellectual disability (ID) are one reflection of the inclusiveness of a community. Our capacity to measure attitudes towards this important aspect of adult life is limited by the lack of an appropriate instrument. The aim of this study was to continue the development of a recently published questionnaire and to establish normative data. Method: The "Attitudes to Sexuality Questionnaire" ("Individuals with an Intellectual Disability") (ASQ-ID: Cuskelly & Bryde, 2004) was modified slightly and questions about hypothesised stereotypical views of sexuality were added. A community sample of 261 adults completed this modified questionnaire, as well as a shorter version of the questionnaire about attitudes to sexual expression in typically developing adults. Results: Factor analysis revealed one general factor associated with sexual rights, plus three other factors related to parenting, non-reproductive sexual behaviour, and self-control. There were few differences in attitudes towards male and female sexuality, and attitudes were only slightly less positive for individuals with an ID than for those without a disability. Views about parenting by people with an ID were more cautious than for other aspects of sexuality. Conclusions: The present study established the factor structure of an instrument for measuring attitudes towards the sexual expression of adults with an ID and provided normative data. Community attitudes towards the sexual rights of adults with an ID are generally quite positive. (Contains 3 tables.)