1. The concentrations of a number of plasma proteins in patients with haemochromatosis were determined by quantitative immunoelectrophoresis, particular attention being paid to the three iron transporting proteins.
2. Transferrin and haptoglobin were within normal limits; haemopexin was significantly greater than normal (P < 0·001).
3. Other changes observed were a significant (P < 0·001) increase of α1 antitrypsin, of α2 macroglobulin and β1A-C; these changes are discussed.