Abstract The early stage of rouleaux formation, which can be observed on a microscope slide, was assessed quantitatively for pairs of cells forming adhering doublets. Previous work on normal cells in normal plasma has been extended to blood samples from patients with multiple myeloma, a blood disorder with a large component of high molecular weight immune plasma protein. Cine film records were obtained for each of 19 pairs of cells which made adhesive contact in a cell suspension diluted by myeloma blood plasma. Analysis, restricted to the events of sliding contact between cells, revealed an approximate doubling of peak sliding velocity, a marked reduction in time to half complete sliding interaction (13 compared to 56 sec for normal cells), and a high variance when comparing sliding velocity as a function of position of overlap. We invite consideration that circumstances of low or zero fluid shear rate that can occur in the venous side of the circulation might have a transient but profound affect on local blood viscosity.