Emergency management is a field in which collaborative activities are inescapable. Emergency planning and response increasingly involves a diverse array of actors across field (emergency management, public health, law enforcement, etc.), sector (government, nonprofit, and for-profit), and level of government (local, state, and federal). The necessity of collaboration is built into the logic of escalation in the Stafford Act and the nature of emergency events as boundary spanning threats. While the necessity of collaboration is clear, the dynamics of this collaboration are less well understood. This paper assesses the temporal dynamics of an emergency management network in a moderately sized community in central Texas. The evolution of the network between 2000 and 2009 make clear that actors are both quick to join and to leave the network while the network maintains its centralized character throughout the time period