This paper reports the results of a multielement analysis of postmortem samples of Menkes patients, of which one was untreated and two had been treated for various lengths of time with intramuscular injections of copper-EDTA. The findings have been compared with data from a Menkes fetus and from controls.The results confirm that copper accumulates in various tissues and demonstrate a further increase in copper levels as a result of the treatment with copper-EDTA. Although no clinical improvement was observed, the levels of some copper-containing enzymes normalized during the copper therapy. Furthermore, in agreement with the identification of the copper-binding protein in the kidney as metallothionein, it was found that not only copper, but also zinc, cadmium, and mercury are trapped in this tissue.A low copper concentration in the brain was also found in a Menkes fetus, indicating that brain damage might already have occurred before birth.