Like most public managers nowadays, local emergency managers operate within complex, uncertain environments. Rapid changes in the scope and severity of the issues increase the extent of intergovernmental collaboration necessary to address such challenges. Using a large data set of county emergency management agency directors, variations in intergovernmental collaboration reflect influences from problem severity, managerial capacity, and structural factors. The results demonstrate that public managers who perceive problems as severe, possess specific managerial skills, lead high-capacity organizations, and operate in less complex agency structures collaborate more often and more effectively across governmental boundaries.