Abstract Good agreement was obtained between an electrophoretic and an immunoprecipitation method for serum albumin, and it is suggested that these offer a means of determining serum albumin concentration with reasonable accuracy. The methyl orange dye-binding method tends to give slightly higher results in disease and occasionally larger discrepancies as compared with the electrophoretic and immunoprecipitation methods, but results are little affected, if at all, by the presence of large amounts of paraproteins. The dye-binding method appears to be ideal for population surveys.