The ability to predict the movement of cohesive sedmient within coastal, estaurine or inland waters has a significant economical and ecological importance in the development of new engineering works and the maintenance of existing installations. This work includes the main processes of cohesive sediment behaviour, namely, erosion, transport, deposition and consolidation. Sub-sections are given on knowledge and procedure where possible. The knowledge section presents data intended to show the practising engineer which parameters are important in each of the above processes. The procedure section gives practical methods for estimating the rates of erosion, transport, deposition and consolidation of the site conditions.