Inflammation of the Achilles tendon and its contiguous structures is one of the most common overuse problems seen in runners. There are actually several etiologies. Involvement of the tendon itself is secondary to areas of mucinoid or fibrotic degeneration, or may be a result of a partial rupture. The sheath (or mesotenon) may also become chronically inflammed. Retrocalcaneal bursitis seems to be a separate entity with hypertrophy and fibrosis of the bursa usually occurring in conjunction with a prominent posterior superior angle of the os calcis. The vast majority of patients can be successfully treated nonoperatively; however, there is a group of patients who are refractory to nonoperative management who would like to continue running, particularly if they are competitive. A retrospective review of 45 surgical cases in 37 patients was performed. All but two of these patients were competitive long-distance runners. There were 24 cases of Achilles tendinitis and/or tenosynovitis, 14 cases with retrocalcaneal bursitis, and 7 with a combination of both. Mean followup was 3 years (range, 1 1/2 to 8 years). Overall there were 87% satisfactory results. Ninety-two percent of the patients with involvement with the tendon and/or sheath had a satisfactory outcome as compared with 71% of patients with retrocalcaneal bursitis. Passive dorsiflexion in the 29 unilateral cases improved from a mean of 17 degrees preoperatively to a mean of 25 degrees postoperatively. We feel that surgery offers a solution for highly motivated runners with chronic posterior heel pain who would like to continue running when conservative measures have failed.