The purpose of this review is to highlight the importance and fields of application of knowledge of currents in environmental studies. Several topics are successively addressed: they include current measurement techniques and the possibilities and applications of existing models (dispersion, sediment transport, primary and secondary production...). Some uses in the field of coastal engineering, water quality management, coastal management, oceanographic studies, etc. are briefly described. The conclusion is that knowledge of currents is a compulsory stage in all coastal environmental studies.