We present a 3 year follow up of a new type of hyperalphalipoproteinemia with stable high density lipoprotein (HDL) concentrations around 6.0 mmol/l in a female with persistently elevated erythrocyte sedimentation rate (ESR). By density gradient ultracentrifugation, next to the intensively colored HDL2-fraction, an additional band between HDL3 and the serum proteins was seen consistently. The patient's plasma contained an unique complex of albumin with apoprotein A-I. Her IgM was 3- to 4-fold elevated was not complexed to HDL. Familial forms of hyperalphalipoproteinemia could be excluded. As a presumed reason for the existence of the HDL-albumin complex we found that the patient's post-heparin plasma lipoprotein lipase activity was over 2-fold increased, while that of hepatic lipase was over 2-fold decreased: no common cause for the existence of the albumin complex and the increased concentration of IgM was found.