Abstract:The logistical challenge of coordinating natural resource management actions across large scales is typically complicated by the diversity of stakeholders' interests. Devising a plan is difficult. Getting diverse stakeholders to agree to and adhere to any logistical solution is harder still. Hence logistical solutions to large-scale problems involve a combination of coordination, and trust-building and contestation which are two key features of collaboration. We studied networks based on stakeholder participation in institutional responses to agricultural pest and disease incursions, where the spatial complexity of response is further challenged by the need to design and implement plans quickly in order to stop Balancing collaboration with coordination 331 the spread of incursions. Using data from the 2010 Australian myrtle rust incursion, we used novel statistical network methods which showed that policy forums at national scales, where higher-level decisions are made, were associated with denser overlapping stakeholder interactions signifying collaboration (bondingcapital, high transaction-costs). Our qualitative data unpacked this, showing how at times uncertainty in process and information is used by some stakeholders to contest decisions at national scales. We failed to find statistical evidence that at local scales, where plans are implemented more-or-less at face value, networks exhibited lower-transaction cost interactions associated with the socially cheaper task of coordination (bridging-capital, low transaction-costs). By identifying the mix of coordination and collaboration in networks for solving environmental problems, capacity building can be more targeted, and rules-of-behaviour can be developed that better fit the requirements of the diverse tasks involved.