Parkinsonism is a rare neurological complication of cancer treatment. Although individual case reports of this syndrome have been reported, the clinical features and prevalence of this syndrome are unknown. We present 3 patients, encountered over 6 months at one institution, who developed parkinsonism after treatment with various chemotherapeutic agents. Parkinsonism was severe in 2 patients, affecting postural reflexes, speech, and swallowing. All 3 patients responded dramatically to treatment with levodopa, and parkinsonism spontaneously improved or remitted over months. This unusual complication of cancer therapy is treatable and may be underappreciated. (C) 2002 Movement Disorder Society.