In clinical practice, we have come across people with intellectual disability who have gender dysphoria and cross-dress. Here, we review the literature on this subject and present an illustrative case example. We searched databases, followed-up references from relevant articles, and contacted colleagues in the field. We found nine papers with case examples and one survey. Gender identity problems certainly occur in people with intellectual disabilities, and developmental perspectives are important in assessing and treating them. In some cases autistic spectrum disorder was co-morbid, for individuals with and those without intellectual disability. Aggression was also common. Documented treatments were primarily psychological and social and did not include hormones and sex reassignment surgery. Capacity to consent is a factor that determines treatment.