Nitroaromatic compounds are partly or fully degraded by a wide range of microorganisms. For this reason, a growing interest in the degradative characteristics of bacteria and fungi towards nitroaromatic compounds has emerged. This interest is aimed at exploiting these capacities to remove nitroaromatic compounds from the environment, or better, to prevent their release. Another potentially beneficial aspect of the great diversity in metabolic pathways involved in the degradation of nitroaromatic compounds is found in possible biotechnological applications. Nitroaromatic compounds may be used as cheap feedstocks in the biocatalytic production of valuable products by enzymes or intact cells involved in their conversion. This paper concentrates on these biocatalytic aspects and deals with research aimed at the production of catechols from nitroaromatic compounds.