The 3rd International Conference on Ship Manoeuvring in Shallow and Confined Water will focus specifically on Ship Behaviour in Locks because it is an actual topic that merits attention. A significant number of locks for large sea-going vessels are being designed or under construction all over the world. The new Panama Canal locks are the most famous example for seagoing vessels. With regards to inland shipping, the adaptation of existing canals requires continuing renovation of existing lock complexes. Lock manoeuvres involve more than just shallow water and bank effects. A series of additional effects such as density currents and the permeability of structures also have to be considered. Ultimately, complex ship hydrodynamics are involved, which are not yet fully understood. Several specific topics can be distinguished such as the behaviour of ships approaching and entering lock chambers, the design of approach lanes to the locks in order to reduce wave reflection and lateral forces and the development of more realistic ship lock simulation models. After successful conferences on bank effects (Antwerp, May 2009) and on ship ship interaction (Trondheim, May 2011), the Third Conference on Manoeuvring in Shallow and Confined Water will have a non-exclusive focus on Ship Behaviour in Locks. This conference will be organised by the Royal Institution of Naval Architects, Flanders Hydraulics Research and Ghent University Maritime Technology Division.