A mobile telemedicine system was designed, implemented, and tested for real-time diagnosis during ambulance transport. The system uses multiple public wireless cellular phones to transmit video and patient biosignals from a moving ambulance to a hospital and delivers to the desktop computer of the receiving physician. The mobile unit on the ambulance is turn-key operated and has an image selection controller for paramedics to send images at specific times and to capture images at high frame rates. The mobile telemedicine system was installed on two ambulances and was successfully used in diagnosing acute ischemic stroke during the transport of six patients. Using the system, stroke specialists were able to remotely conduct neurological examinations which required evaluation of facial expressions and movement of arms and legs. Questionnaires completed by four users (two paramedics and two stroke specialists) of the mobile telemedicine system indicated that (1) the system did not intrude into the privacy of the patient or the paramedics, (2) it was easy to use, (3) it was adequate for conducting clinical examinations, and (4) it conveyed critical clinical information.