Autoreactive B cells and plasma cells appear to be of central importance in the pathogenesis of systemic lupus erythematosus (SLE) characterized by a plethora of autoantibodies. Recent insights into abnormalities of B cell and plasma cell compartments in human SLE have identified a number of cellular disturbances within these compartments that in part correlate with the disease activity. This review discusses these findings and the potential underlying extrinsic and/or intrinsic influences apparently driving general B cell activation in this entity.