The need to develop successful collaborative strategies is an enduring problem in sustainable resource management. Our goal is to evaluate the relationship between information networks and conflict in the context of collaborative groundwater management in the rapidly growing central highland region of Arizona. In this region, water-management conflicts have emerged because of stakeholders' differing geographic perspectives and competing scientific claims. Using social network analyses, we explored the extent to which the Verde River Basin Partnership (VRBP), which was charged with developing and sharing scientific information, has contributed to collaboration in the region. To accomplish this, we examined the role that this stakeholder partnership plays in reinforcing or overcoming the geographic, ideological, expert, and power conflicts among its members. Focusing on information sharing, we tested the extent to which several theoretically important elements of successful collaboration were evidenced by data from the VRBP. The structure of information sharing provides insight into ways in which barriers between diverse perspectives might be retained and elucidates weaknesses in the partnership. To characterize information sharing, we examined interaction ties among individuals with different geographic concerns, hierarchical scales of interest, belief systems (about science, the environment, and the role of the partnership), and self- identified expertise types. Results showed that the partnership's information-sharing network spans most of these boundaries. Based on current theories of collaboration, we would expect the partnership network to be conducive to collaboration. We found that information exchanges are limited by differences in connection patterns across actor expertise and environmental-belief systems. Actors who view scientists as advocates are significantly more likely to occupy boundary-spanning positions, that appear to impede the success of the partnership. This analysis challenges widely held assumptions about the properties that separate successful collaborations from those that are less successful. It has implications for our understanding of the factors that constrain information processing, knowledge production, and collective- action capability in institutions.