Using soil enrichment techniques we have isolated micro-organisms capable of degrading simple nitrile compounds. One species identified as an Agrobacterium spp. was examined in detail. This isolate was capable of utilising a range of aliphatic and aromatic nitriles as sole sources of carbon and nitrogen. Assays for enzymes involved in nitrile degradation and growth/production studies with this organism growing on acetonitrile indicated that breakdown occurred via a two step mechanism firstly to the amide and then via the production of the corresponding acid with th subsequent release of ammonia. Our studies indicate that the system of nitrile breakdown is inducible and levels of the amidase are 170 times that of the nitrile hydratase in crude extracts.