The primary focus of this review is the discussion of how biosensor-based platforms can be used in conjunction with microbial cells for monitoring, environmental and industrial applications. Two approaches will be comprehensively discussed. The first of these will examine how immunosensors can be used for the sensitive and selective detection of bacterial pathogens in a range of diverse and complex sample matrices. Secondly, we discuss the implementation of free and immobilised microbial cells for facilitating the analysis of chemicals and metabolites in cost-effective devices that, in turn, are directly applicable to environmental monitoring. Further examples, relating to the uses and advantages of microbial fuel cells are also discussed, with particular emphasis on recent and innovative developments. © 2010 Bentham Science Publishers Ltd. All rights reserved.