Abstract: New PB92 or Subtilisin 309 mutant serine proteases are provided having specific mutations, resulting in an surprisingly better wash performance or in an improved storage stability with at similar or even better wash performance. These PB92 or Subtilisin 309 mutants include mutations at positions 60, 87, 97, 99, 102, 116, 117, 126, 127, 128, 130, 133, 134, 154, 156, 158, 159, 160, 164, 169, 175, 180, 182, 193, 197, 198, 203, 211, and 216. The new proteases, therefore, are very suitable for use in various types of detergents, whether or not in conjunction with other enzymes, for example amylases, cellulases and lipases. Preferred embodiments are the PB92 and Subtilisin 309 mutants having a mutation at position 102 and in particular those having at least one further mutation.