Wilson's disease is an autosomal recessive disorder characterized by progressive cirrhosis or neurological signs. Early detection and prompt treatment can reverse the relentless course of the disease. Treatment with D-penicillamine substantially improves the outlook for such patients unless side effects preclude its use. We report the use of triethylene tetramine dihydrochloride (Trien), a new non-sulfhydryl-chelating agent, in a girl who was unable to tolerate D-penicillamine in spite of steroid coverage. The drug has been well tolerated without side effects for approximately 2 1/2 years. Our patient's favorable clinical response would suggest that Trien is a safe alternative agent for the treatment of Wilson's disease when D-penicillamine is not tolerated.