In this article the author outlines the scope of early intervention services to young children with developmental disabilities, and their families. Discussion centres on how these support services have evolved and how they achieve change. These changes have involved a significant broadening of the aims of early intervention and a heightened awareness of the critical importance of the way in which services are delivered. Early intervention services are no longer exclusively focused on the child's disability but are much more concerned with the child in the context of the family and community. Research findings regarding the effectiveness of services and outcomes for families are presented, and critical factors involved in successful family intervention are identified.