Good communication on a medical team is essential to optimize patient care and reduce human error risk. While this is well documented for civilian medicine, there is a paucity of research in the military prehospital environment (MPE). We analyzed four cases of miscommunication in the MPE: during a casualty handoff, within a team during a tactical medical operation, between a medic and a doctor during a mass casualty event, and in a helicopter while caring for a casualty. One mission had an adverse outcome, another had a rescue team disruption during operations, and two cases had errors without adverse outcomes. In each case, closed-loop communication with readbacks may have reduced or prevented actual or potential patient harm and optimized timely patient care. All branches of military prehospital medicine should employ efforts and techniques that ensure standard, reliable communications during medical operations to prevent adverse patient outcomes.