Drawing on the author's experience carrying out qualitative research in the field of occupational therapy with people with intellectual disabilities, this article explores ethical issues inherent in ethnographic and case study research, where study designs can evolve over time. Such qualitative methodologies can enable deep understanding of research topics, but detailed description of methods and of the range of potential experiences participants may have is necessary to ensure that they are fully informed and ethics committees satisfied. Thorough consideration is required of ethical issues related to topic relevance and design, recruitment, collection of data and portrayal of participants in the eventual case report. The article illustrates a way in which research of this type can be explained and justified, including how recruitment can be achieved of participants likely to lack capacity to consent to participation themselves.