A literature review was carried out to examine what is currently available in terms of theories, literature, and research regarding practitioners who have worked therapeutically with both children and adults with autism spectrum disorder (ASD) and regarding this client group undergoing psychological therapies. It was deemed necessary to include both children and adults as well as both clients with diagnoses of ASD and high-functioning autism spectrum disorder (HFASD) due to the scarcity of research obtainable. Questions raised and indication of research paucity helped form the research questions for the following two investigations. The second year research project investigated the lived experience of practitioners who have worked with adults with HFASD and the third year research project investigated the lived experience of adults with HFASD who had undergone or are undergoing psychological therapies. Both research projects utilised qualitative research methods.