Abstract: There is provided a method and apparatus for bacterial testing, in which a multiple-pin inoculation head picks up bacterial samples in a compartmentalized sample tray and transfers these to a compartmentalized culture plate for incubation. The culture plate contains a test media to which some bacteria are sensitive. An indicator material is also included, which changes color upon pH change due to bacterial growth. The result is a geometric pattern of color, which is entered into a computer storage. Additional culture plates are also inoculated in the same way, each containing a different test medium together with an indicator. After all plates have been incubated and data entered into the storage, a computer facility compares the pattern of sensitivity of the unknown bacteria with known sensitivity patterns of known bacteria to determine the most likely identification for each of the unknown bacterial samples.