Since autism was first recognised as a distinct diagnostic category, prevalence rates have increased considerably. This chapter is aimed specifically for professionals who work with adults with autism who have high support needs. The chapter outlines some of the key issues that may cause obstacle for these adults, such as social relationships and self-advocacy, education, training, and employment, as well as housing and living conditions. Given that most of the available research evidence endorses interventions that are based on the science of Applied Behaviour Analysis (ABA), this chapter describes some concrete examples of these practices for people who require support to achieve their full potential. The chapter closes with specific recommendations for policy and practice.