Abstract: Urban open space provides both social and environmental services that range from ‘private’ to ‘public’ goods. This paper investigates the relationship between urban open space public and private goods and human wellbeing, to identify effective planning and management strategies based on theory and case studies of Ottawa and Canberra. The paper constructs a framework for effective management based on the economic principles of excludability, rivalry and devolved governance. This framework is the basis of an analysis of literature and exploration of unpublished surveys and reports on the gazetting and operation of open space networks in Ottawa and Canberra. Historically, gazetting urban open space provides ‘public’ ecosystem services (i.e. non-excludable and non-rival) however, in operation; these open spaces offer a variety of services ranging from public to private goods. The findings indicate that urban open spaces are most effectively established by government. However in operation, they are more effectively managed collaboratively. By adopting the framework of excludability, rivalry and devolved governance, policy makers can better allocate resources for effective management of urban open space for human wellbeing.