The estimation of serum albumin obtained with SMAR 12/60 by the bromcresol green method are in good agreement with values determined by electrophoresis only in the normal range. Interestingly marked discrepancies occur in the clinically relevant cases of hypalbuminosis. The shortening of the reaction time between bromcresol green and serum results in a better agreement between the values obtained with SMAR 12/60 and the values determined by electrophoresis over the whole range.