Our work present an overview of the various analytical techniques for determining numbers of faecal index and indicator bacteria as well as selected pathogens in water samples. It includes conventional and new (principally molecular biology) techniques and outlines the performance characteristics of the different methods. Our work describes the more “classical” methods, witch depend largely on cultivation techniques, as well as molecular methods. The majority of the methods presented here have already proven to be useful in drinking water microbiology or display great potential. In the detection, identification and quantification of target organisms some approaches are solely based on a single technique whereas other strategies take advantage of a combination of different methods. For example, to identify Escherichia Coli reliance can be placed on one day cultivation on chromogenic media. Alternatively, in a much faster approach, short precultivation on an artificial medium can be combined with labeling using fluorescent probes and microscopy. On the horizon are methods based on micro arrays and biosensors. Advances in semiconductors and computers are expected to allow the next generation of microbial sensors to be small and simple devices, witch are quick to respond. The future thus holds the promise of new techniques for detecting both existing and emerging pathogens