For the last 30 years, positive behavioural support (PBS) has experienced considerable growth as the approach has been applied with an expanding number of populations and, more importantly, at multiple levels of implementation (Dunlap et al., 2009; Lucyshyn et al., 2015). In the USA, PBS began as a focused approach for resolving serious challenging behaviours of individuals with severe developmental disabilities, including autism, and grew into an approach that included implementation of strategies aimed at groups of children in classrooms and schools, as well as children and adults (beyond those with severe developmental disabilities) in a variety of early education and service systems. In this article, we will discuss the defining features of PBS and the cultural and contextual frameworks within which PBS operates. Preschool, school age and adults with developmental disabilities systems will be shared and one US state, Nevada, will provide an exemplar of how PBS can effectively respond to a number of different needs across agencies and systems. Finally, barriers and enablers to the future growth of PBS will be discussed. (author abstract)