Metastatic plexopathy is often a disabling accompaniment of advanced systemic cancer and may involve any of the peripheral nerve plexus. 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, carcinomatous plexopathy typically is associated with severe unrelenting pain as the cardinal clinical feature. Later, weakness and focal sensory disturbances occur in the distribution of plexuses involvement. Epidural tumor involvement frequently (in more than 50% of patients) coexists with either plexopathy. 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 and chemotherapy. In selected patients, 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, to maximize remaining neurologic function, and to prevent complications of immobility produced by the neuromuscular dysfunction.