Estuaries are large bodies of water within which interactions of physical, chemical, and biological processes with suspended and bottom sediments are complex. The goals of estuarine sediment transport research are broad and place diverse requirements on instruments and methods of observation. Processes of sediment advection often are investigated with methods that provide synoptic observations over expanded geographical regions, i.e., remote sensing and rapid shipboard reconnaissance techniques. In constrast, time series data collected within an estuary by anchored ships or by moored or semipermanently emplaced instruments are used for the study of the processes or mechanics of sediment resuspension and deposition. Understanding the mechanics of estuarine sediment transport also provides important insights into the regional or advective processes active in estuaries. This paper reviews the present status of methods used for sediment transport research in estuaries. It explores some fundamental sediment transport equations to define measurement requirements, describes various classes of instruments to meet the measurement requirements, and presents examples of individual instruments that have been combined into opertional measurement systems. Some potentially important methods under development are also discussed. ¿ American Geophysical Union 1989