A bacterial strain capable of degrading 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) was isolated from insecticide-contaminated soil by biphenyl enrichment culture and identified as a Pseudomonas species. The organism degraded DDT through the intermediate formation of 2,3-dihydroxy-DDT, which undergoes meta-ring cleavage, ultimately yielding 4-chlorobenzoic acid as a stable metabolite.