The design, construction and field application of systems for collecting samples of suspended material in tidal waters over an intertidal zone are described. Each sampler consists of: a tower framework; sample containers for the water-sediment mixture; and a series of mechanical or electromechanical release mechanisms to control the instant of sampling (in relation to the tidal cycle). The suspended-sediment sampling systems were used over 40 tidal cycles across an intertidal flat in the Wash. The systems have demonstrated that an extensive sampling programme can be undertaken at low cost and using minimum manpower in the field. However, it is also considered that the mechanisms and sampling techniques described have broader applications in estuarine and oceanographic investigations.