Abstract: This invention relates to bioluminescent methods for detecting specific target bacteria, such as E. coli, coliforms, Enterococcus spp, Listeria spp and S. aureus in samples. The sample to be tested is incubated in a non-selective growth medium for up to 8 hours to produce a sample culture and which is then mixed with detection reagents. The detection reagents include a lysis reagent which disrupts bacterial cells in the sample, a pro-luciferin molecule which is specifically converted into luciferin by said target bacteria; and luminescence reagents which produce a luminescent signal in the presence of luciferin. The mixture of sample culture and detection reagents is then incubated and the luminescent signal from the reaction mixture measured.