The association of vasculitis and asymptomatic primary biliary cirrhosis (PBC) was documented in a 39 year old female. Cyclophosphamide was used with good results. The Raji cell assay for circulating immune complexes (CIC) was positive initially with further values changing in parallel with disease activity. The C1q binding assay failed to reveal significant levels of CIC at any time. Lymphocytotoxic antibodies were not detected in the serum. Sucrose density ultra-centrifugation experiments revealed 9-17S material in sera that were positive for CIC by the Raji cell assay. We conclude that intermediate size CIC may be important in the pathogenesis of the vasculitis associated with PBC.