A large number of containers (approximately 1500 containers) are fallen over board annually due to different reasons such as encountering heavy weather, collision with the other vessels or grounding which consequently cause serious problems and difficulties such as: (1) Endangering the safety of navigation, reducing the depth of the channels, (2) Damaging the environment (rocks, coral), (3) Endangering the life of fishes and underwater species, (4) Pollution, as numbers of containers are loaded with dangerous chemicals, (5)Debris washing up beaches making beaches dirty endangering environment and tourism industry, (6) Damaging the fishermen nets, (7)Wasting a lot of time and manpower, including the use of highly technical equipment, to find and recover them and (8) Unnecessary additional costs to the ship owners/charterers.The containers are loaded on the container ships/general cargo vessels by calculating several factors such as: stability of the vessel, lashing requirements of containers,stack loads, dangerous good compliance with International Maritime dangerous Good code (IMDG), wind effect, minimum visibility. A bay plan is the plan which describes the position of all containers on board a ship, whether inside cargo holds or on top of the hatch covers. It has come to author’s mind of fitting a tracking device outside the container. The proposed device can be named"Container Automatic Tracking System (CATS)".