Initially an eleven variable, sixteen assay 2(15-11) fractional factorial design, was used to determine the key factors in the production of violacein produced by Chromobacterium violaceum, CCT 3496. Subsequently five and three factor central composite designs were executed to determine response surfaces with the aim of optimizing cellular mass and crude violacein production. The 7.5 g l(-1) dry cell mass and 0.17 g l(-1) crude violacein productions obtained with our initial culture medium were increased to 21 g l(-1) and 0.43 g l(-1), respectively, for a medium investigated in the three factor design.