Sports injuries to the hip and groin region have been noted in 5% to 9% of high school athletes. These injuries occur most commonly in athletes participating in sports involving side-to-side cutting, quick accelerations and decelerations, and sudden directional changes.Symptoms may range from intermittent episodes of mild discomfort to severe and chronic career-ending pain. Groin injuries may result from a variety of causes. Although this article deals mainly with athletic etiologies, the physician must keep in mind that many other medical conditions may also affect the groin. Because of these overlapping medical conditions and because the anatomy of the region is so complex, a team approach is optimal. In Part 1 of this two-part series, ligament/muscle strains, nerve entrapment syndromes, and posterior abdominal wall abnormalities are reviewed as common causes of groin pain.