Emissions of volatile sulfur compounds (VSCs) including hydrogen sulfide (H2S), methanethiol (MT), dimethylsulfide (DMS), and dimethyldisulfide (DMDS), referred to collectively as reduced sulfur compounds (RSCs), occur from a host of anthropogenic sources including the pulp and paper industries, refineries, petrochemicals, sewage treatment plants, etc. This article is organized to provide an overview of the biotreatment processes for VSCs with an emphasis on biofiltration in the pulp and paper industry. To this end, we discuss up-to-date knowledge on the generation of sulfurous odorants and their microbial degradation processes in biotreatment techniques. The fundamental characteristics of such techniques are described with respect to the configuration and design of the bioreactor treatment facilities and the associated mechanisms of operation. Finally, we add our perspectives on,future research and development needs in this research area. (C) 2014 Elsevier Ltd. All rights reserved.