The goal in managing many musculoskeletal injuries is now early mobilization-not immobilization. This shift in emphasis encompasses injuries ranging from a strained back to a sprained ankle. Patients with sciatica who previously might have been kept at bed rest for several weeks are now encouraged to avoid bed rest and to alleviate nerve irrita- tion with positional exercises. Similarly, patients with ankle sprains gain faster pain relief and recover function more rapidly when cast or splint immobilization is avoided. Early mobilization is appropriate for many acute injuries without risk of significant bone or joint instability. Its advantages have emerged as the many detriments or hazards of even brief periods of immobilizing muscles, joints, and bones have become apparent. In the following pages, I present cases that clearly demonstrate the risks of immobilization. Several of these cases underscore the dangers of immobilizing injured soft tissue, which continues to swell after a cast or splint has been applied. Wrist Injury Problems in the wrist can occur when a displaced distal radial fracture or Colles fracture is treated in a cast with the wrist in maximum flexion to hold the reduction. As the photograph shows, this can cause both compression of the median nerve that leads to carpal tunnel syndrome and, occasionally, a compartment syndrome with subsequent impairment of the intrinsic musculature of the hand. Immobilization of this patient's wrist in a hyperflexed position for a Colles fracture resulted in atrophy of the thenar muscles, with some loss of hand function. The acutely fractured distal radius is best immobilized in a temporary splint with minimal wrist flexion until the acute swelling subsides. At that point, you can safely apply a circular cast that maintains reduction without hyperflexing the wrist and risking nerve or muscle damage.