Abstract: An apparatus for prompting an operator in the performance of cardio pulmonary resuscitation. The apparatus comprises a casing housing, a keypad with input switches, a display with light emitting devices, audible buzzers and a control circuit embodiment in a programmed microprocessor and associated circuitry. Input prompting signals are controlled by the control circuit to prompt the operator to ascertain the presence of a pulse of the casualty, specify the number of rescuers performing the resuscitation, and specifiy the age status of the casualty. The control circuit prompts the operator to perform either or both heart compression and lung inflation on the casualty at a prescribed rate.