Metastatic plexopathy is often a disabling accompaniment of advanced systemic cancer and may involve any of the peripheral nerve plexuses. Brachial plexopathy most commonly occurs in carcinoma of the breast and lung; lumbosacral plexopathy is most common with colorectal and gynecologic tumors, sarcomas, and lymphomas. Regardless of the location, neoplastic plexopathy is often characterized by severe, unrelenting pain. Later, weakness and focal sensory disturbances occur in the distribution of plexus involvement. In previously treated patients, the main differential diagnostic consideration is radiation-induced plexopathy. Treatment of metastatic plexopathy is palliative and includes radiotherapy to the tumor mass, chemotherapy, and symptomatic treatment. In selected cases, subtotal surgical resection of the tumor may be warranted. The response to therapy is modest and generally short-lived. Efforts should be made to provide adequate pain control, maximize remaining neurological function, and prevent complications of immobility produced by the neuromuscular dysfunction.