Swimming has become a popular recreational activity as well as a highly competitive sport in the United States. The repetitive nature of swimming can predispose the shoulder to mechanical impingement and microtrauma, which may lead to laxity, rotator cuff fatigue, and subsequent secondary impingement. Improper stroke mechanics can place the swimmer's shoulder at further risk. The purpose of this paper is to describe the pathology of secondary impingement in freestyle swimmers and to discuss the clinical implications for rehabilitation of swimmers with the pathology. A thorough subjective and objective evaluation is necessary to design a successful rehabilitation program. The rehabilitation program for swimmers with secondary impingement includes modification of training, flexibility, range of motion, strengthening, and mobilization as indicated. Functional and proprioceptive training may also be useful techniques in the rehabilitation of swimmer's shoulder. Improper stroke mechanics can also have clinical implications on swimmer's shoulders with secondary impingement. The clinical implication of secondary impingement in freestyle swimmers suggests that the primary goal of rehabilitation is to promote equilibrium of the shoulder complex while accounting for the demands of the sport.