Partnerships represent a prescriptive form of network governance, based on the idea of cooperation. This article has four aims. The first is to describe why network governance and partnerships are important now, and what one particular example - Primary Care Partnerships - is addressing. The second is to analyse the network structure of two of these partnerships, and the third is to examine network dynamics. The fourth aim is to explore relationships and sustainability over the longer term. Two government-funded and steered partnerships, which were established to increase coordination between primary care services in Victoria, Australia, were examined. Annual interviews at three points in time between 2002 and 2005 were used to explore relationships between organizations within these two partnerships. The structure of two different communication networks, based on contacts for work and contacts for strategic information, were examined using social network analysis. Tracing network structures over time highlighted partnership dynamics. The network structures changed over the three years of the study, but an important constant was the continuing centrality of the independent staff employed to manage the partnerships. Over the longer term, it seems to be more important to fund independent partnership staff, rather than people who connect partnerships to the funding agency. If partnerships are seen as valuable in improving service coordination and health outcomes, then long term rather than just start-up funding support is required.