Because of the extraordinary technological progress made over the past years in pulse generators, the objective and indications of definitive cardiac pacing have greatly changed. All the different advantages are aimed at mimicking the electrophysiological and mechanical conditions of normal heart function. We have seen the development of: DDD mode dual chamber pacemakers, which in cases of AV block recreate normal AV synchrony; single chamber rate-responsive units piloted by an external captor responding to the organism's metabolic needs (intra-corporal vibrations resulting from exercise, respiratory rate, minute ventilation, QT interval, central temperature, SV O2...); they provide effective correction of atrial (AAI-R mode) or ventricular (VVI-R mode) chronotopic incompetencies often associated with chronic conduction disorders which make it impossible for patients paced in VVI or AAI mode to adapt heart rate to exercise level; and finally, "universal" pacemakers capable of pacing in all the single or dual chamber modes with rate responsiveness to one or several captors. These new pacemakers offer adaptability to the paced patient's needs as they vary throughout his lifetime. These units will probably be the "standard" cardiac pacemakers of the future.