Ninety consecutive women with unilateral Colles' fractures were randomized into two different treatment groups. The control group was treated for 5 weeks in conventional short-arm, below the elbow plaster of Paris casts. The other group (N = 45) was treated similarly in plaster casts for 3 weeks and then had flexible casting applied for the remaining 2 weeks which allowed for early joint mobilization. Functional recovery was assessed by measuring grip strength and joint mobility at intervals over the 3 years. Radiographic and overall assessments were also made during 3 year course of study. Virtually all patients reported greater comfort after switching to the flexible casting. Mean grip scores and joint mobilities were higher at all time points with early mobilization, reaching levels of statistical significance at 6 months for grip score and at 3 months for joint mobility. By 3 years most differences between treatment groups had resolved. We found no evidence that early mobilization was detrimental to recovery. We conclude that early mobilization is a satisfactory treatment option for Colles' fracture, and may, in fact, hasten functional recovery.