Today the transfer of liquid cargoes from ship-to-ship at sea is a commonly used practice. In recent years Ship to Ship Operations (STS) have proven to be safe given that proper procedures are implemented and suitable equipment is used. This course is intended to provide the main aspects of planning and execution of STS operations and is useful for Masters Deck Officers Superintendents and other parties engaged in STS operations such as ship charterers traders and STS service providers.