The fundamental responsibilities of Emergency Medical Service (EMS) systems are to provide urgent medical care, such as pre-hospital care, and to transport the patient to the hospital if needed. The agility and efficiency of EMS systems are major public concerns. Since the EMS process involved is fundamentally a transportation process, the Lean Transportation approach is a viable option for improving Emergency Medical Service (EMS) operations performance. The identification of waste during the ambulance cycle time is the basis for designing an operations improvement strategy. The scheme utilized uses modified versions of the Transportation Value Stream Map (TVSM) and The Operational Vehicle Effectiveness (TOVE) Index. Thus, availability, performance and quality wastes are identified to define the improvement strategy. Results of the application for the Monterrey metropolitan operations of the Mexican Red Cross are provided.