The scopes of the session involve different aspects of the large-amplitude wave phenomena in the Ocean such as freak or rogue waves, storm waves; large-amplitude edge and internal waves: dynamical and statistical theories, field observations and laboratory modelling, numerical simulations in the frameworks of approximate and primitive equations. Special attention is paid to the description of the wave breaking process, and also large-amplitude wave interaction with coastal structures. An essential concern of the session is all kinds of sea hazards related to marine operations: extreme storm conditions, collisions with abnormally high and steep solitary waves, etc. The session is addressing also wave description for marine structure design. General marine extremes such as climate change, tropical cyclones are in the focus of the session as well.