Anterior cruciate ligament (ACL) reconstruction is a commonly performed operation. A variety of graft options are used with the most popular being bone-patellar-tendon-bone and hamstring autograft. There has been an increase in the popularity of hamstring autograft over the past decade. The aim of the study was to assess the ten year subjective knee function and activity level following four-strand semitendinosis and gracilis (STG) anterior cruciate ligament reconstruction. 86 patients underwent anterior cruciate reconstruction by two knee surgeons over a 12 month period (January 1999 to December 1999). 80 patients meet the inclusion criteria of arthroscopic ACL reconstruction. The same surgical technique was used by both surgeons involving four-strand STG autograft, single femoral and tibial tunnels and aperture graft fixation with the Round headed Cannulated Interference (RCI) screw. Patient evaluation was by completion of a Lysholm Knee Score and Tegner Activity Level Scale at a minimum of ten years from reconstructive surgery. This was by initial postal questionnaire and subsequent telephone follow-up. 80 patients underwent anterior cruciate reconstruction with average age 30.9 years (15 to 58 years). There was a 77.5% (62 patients) response at ten years to the questionnaire. The median Lysholm Knee Score at ten years was 94 (52 to 100). The median activity level had decreased from 9 to 5 at ten years according to the Tegner Activity Scale. 73% of patients reported a good or excellent outcome on the Lysholm score. The group of patients was further divided into those that required meniscal surgery and those that did not. The patients that did not require meniscal surgery had a median Lysholm score of 94 and those that required meniscal surgery had a similar median Lysholm score of 92.5. However it was noted that 8 patients required medial and lateral partial menisectomies at the time of original reconstruction. This group of patients had a median Lysholm Knee Score of 83.5 and Tegner Activity Scale of 4 at ten years following reconstruction. 17 of the 62 patients (27.4%) required re-operation because of further knee symptoms, with 4 patients requiring revision of the anterior cruciate following re-rupture. In conclusion anterior cruciate ligament reconstruction with four-strand STG hamstring autograft provides a reliable method of restoring knee function, with a 6% revision rate for re-rupture at ten years. Combined partial medial and lateral menisectomy at the time of the initial reconstruction is a poor prognostic indicator of function at ten years.