A new family with an electrophoretically more slowly moving albumin variant is described. The pattern of variance was studied using three different electrophoretic techniques, and compared with certain other known fast and slow variants. Features of penicillin and bromphenol blue binding by normal and variant albumins were also studied. Both normal human albumin and the albumin variant treated with penicillin broadened and moved faster. Native albumin A, prestained with bromphenol blue, binds approximately twice as much of the dye as the slow-moving variant. On the other hand, staining of denatured proteins on paper showed that both bands take up equal amounts of dye.