Rating of perceived exertion (RPE) is endorsed by the American College of Sports Medicine as a useful adjuvant for prescribing and monitoring exercise intensity. In this paper, I describe a rationale for the use of RPE and other exertional symptoms as an alternative to traditional exercise prescription procedures for healthy adults. Errors associated with using RPE for producing exercise intensity are discussed along with limitations with the use of HRReserve as the standard for judging the accuracy of RPE for prescribing relative exercise intensity. The concept of preferred exertion is discussed as a prescription paradigm that is complementary to the use of perceived exertion and physiological indicators of relative exercise intensity. Important areas that have not received enough research attention are summarized.