Primary systemic amyloidosis (PSA) is a plasma cell dyscrasia. Organ damage is caused by deposition of amyloid, derived from monoclonal light chains, in tissues including nerves. PSA damages tissues and leads to combinations of neuropathy and renal, cardiac, and liver failure. The neuropathy of PSA is relatively stereotyped with damage to small and autonomic nerve fibers and superimposed carpal tunnel syndrome. The disease is progressive and mortality is high, especially when there is early involvement of vital organs. Treatment in the past was relatively ineffective. However, with the advent of peripheral blood stem cell transplantation and chemotherapy in selected patients, prolonged survival is possible if the weight of organ damage at onset of treatment is not too high. Thus, early detection is paramount.