Seventy-five patients undergoing arthroscopically-assisted anterior cruciate ligament reconstruction by the same surgeon were divided into three random subgroups. All of the anterior cruciate ligament reconstructions used the middle third of the ipsilateral patellar tendon autograft. Patients undergoing meniscal repair, extraarticular procedures, or repair of other ligaments were excluded. The 75 patients were divided into subgroups to assess the benefits or disadvantages of early active motion (25 patients), continuous passive motion (25 patients), and a combination of both (25 patients) during the first 30 days after surgery. All patients were evaluated at specific intervals for 6 months after surgery. Data recorded included drain output, medication usage, tourniquet time, leg involved, hospital stay length, KT-1000 testing (before surgery in the anesthetized patient, after the procedure was completed, and 2 and 6 months after surgery), and range of motion. Radiographs and the International Knee Evaluation Form were also used to evaluate the results. No statistically significant differences were found between the three groups. Side-to-side anterior-posterior differences, stability, and restoration of full range of motion were similar in each subgroup at each evaluated interval. In this prospective study of motion, started immediately after anterior cruciate ligament reconstruction, passive and active methods were shown to have identical results. A supervised active and passive motion program during the 1st month had the same results as either one used individually.