Providers of emergency medical services (EMS) must communicate vital information during critical phases of operations. Errors in communications, for example, the failure to hear a directive, will compromise safe and effective patient care. This article presents a case that resulted in litigation because of communication failures during the interfacility transfer of a trauma patient who subsequently died in the ambulance. The communication failure involved members of a ground ambulance crew, their dispatcher, and a supervisor. The failure of the emergency medical technician (EMT) who was driving to hear from the treating EMT and her dispatcher vital information pertaining to changes in their destination and of plans to intercept another ambulance, or alternatively, the driver's ignoring this information, led to a delay in care and may have contributed to the patient's death. Factors contributing to the cause of this communication failure may have been related to the nature of the EMS setting: the physical separation between crew members (the driver, and the care provider in the back of the ambulance); the noise of the ground ambulance transport environment, most notably, the siren; and the stress of treating a patient in critical condition. The case highlights the importance of using structured forms of communication, specifically the read-back tool and the critical assertion strategy, to limit failures in communication during EMS operations and in operations in other high-risk medical settings.