Background: This paper considers the challenges regarding the development and use of self-report tools for sensitive, personal topics, in this case experiences of death and bereavement for individuals with intellectual disabilities (ID). These challenges are represented through the experience of the development of a self-report measure of complicated grief for use with individuals with intellectual disabilities. Materials and method: Focusing on the topic of bereavement, and using a case study format, this paper describes the development of a self-report measure for complicated grief. Results: Following three phases of questionnaire development, the Complicated Grief Questionnaire for People with Intellectual Disabilities (CGQ-ID) was adapted for use as a self-report measure with individuals with intellectual disabilities. The development process, informed by recommendations in the research literature, provides evidence that self-report is possible with individuals with intellectual disabilities even when the topic is as sensitive as bereavement and when abstract concepts such as emotions are involved. Conclusions: The adaptation process described here might provide a useful template for the development of other scales on sensitive topics.