An unusual vertical fracture through the superior articular process of L5 is described in a professional skier. This fracture, not associated with a pars interarticularis defect, is felt to be stress related. Standard oblique radiographs failed to demonstrate the defect but it was seen clearly on steep oblique views. The fracture was the cause of chronic backache to the patient. Followup radiographs after 14 months demonstrated a nonunion of the fracture.