Working with clients with multiple and complex needs represents a significant challenge for drug and alcohol services. Many clients presenting to these services have multiple and complex needs, associated with, but not limited to, cognitive impairment and/or contact with the criminal justice system. This article examines a subset of recent scholarly literature associated with provision of drug and alcohol services to clients with complex needs and its connections with drug and alcohol service provision by non-government drug and alcohol services in New South Wales (NSW), Australia. A limited literature review of scholarly literature related to working with clients with complex needs was undertaken. Publications were included if they specifically discussed policy or programmes associated with multiple and complex needs post-dating 2000. An examination of service provision by metropolitan, regional and remote non-government drug and alcohol services followed the literature review. The scholarly literature around programmes working with clients with complex needs suggests that it is often difficult to disentangle complex needs, such as cognitive impairment and offending behaviour. Five case studies representing real-world practices from the examination draw together the scholarly literature and the landscape of service provision as described by drug and alcohol services in NSW. The aim of this article is to explore the drug and alcohol service delivery landscape in NSW in the context of literature relating specifically to the intersection of complex needs such as cognitive impairment, contact with the criminal justice system and unstable accommodation.