Overuse related tendon pain is a significant problem in sport and can interfere with and, in some instances, end an athletic career. This article includes a consideration of the biology of tendon pain including a review of tendon anatomy and histopathology, risk factors for tendon pain, semantics of tendon pathology, and the pathogenesis of tendon pain. Evidence is presented to guide the physical therapist in clinical decision-making regarding the examination of and intervention strategies for athletes with tendon pain.