Bacterial Identification, first described by Bryant (1986), is a program that provides a novel way of enhancing the teaching of systematic bacteriology and numerical identification procedures. A student is assigned an unknown isolate from a list of bacteria. The student's objective is to identify the unknown isolate using the least number of tests from the set of tests available. Simultaneously the computer tries to identify the unknown using optimised and random selection of tests. A student can compare their progress against that of the computer. The program has been improved and the data matrix on which it was based has been revised by the addition of 14 more species, an additional test and by updating the original probability matrix. The program, Bacterial Identification, is available as ‘freeware’ and has been placed with organisations that distrubute such software.