The existing literature on neighboring state military interventions in civil wars only examines whether they occurred, not how they occurred. I argue that neighboring state military interventions exhibit wide variation at the tactical level and can be empirically differentiated according to the military resources required to carry them out. Using qualitative archival data, I develop a framework to systematically compare this “military resource cost” among actors and across time based on a set of five tactical characteristics that require varying levels of military resources to implement. To demonstrate the viability of this approach and the types of findings it can generate, I identify and apply the framework to all 17 neighboring state military interventions in the DR Congo since the end of the 2nd Congo War in 2003. I find that even within the same conflict area and among the same actors, there is extensive variation in the tactical characteristics and overall military resource costs of the different interventions. This finding suggests neighboring states’ military intervention decisions involve much more complex calculations than just whether to send in the troops.