Developments in Geotechnical Engineering, 23: Stability of Tidal Inlets: Theory and Engineering focuses on all aspects related to tidal inlets on littoral drift shores where freshwater flow is small or non-existing. The selection first tackles the development and configuration of tidal inlets and inlet hydraulics. Discussions focus on flow dynamics and nearshore transport, combinations of waves and currents, sediment transport and storage in the tidal entrance, offsets of tidal inlets, natural inlet regimen, migration of inlets, and origin of tidal inlets. The manuscript then examines sediment transport in tidal inlets, stability of tidal inlets on littoral drift shores, and design and improvements of coastal inlets. Topics cover ocean entrance, overall stability condition, hydraulic and sedimentary principles, non-scouring channels, transport of sediments in wave agitated waters, and sediment transport by combined wave and current action. The publication explores improvements by structures, including natural bypassing, types of improvement, and bypassing by structures and bypassing plants or arrangements. The selection is a valuable source of data for researchers interested in the stability of tidal inlets.