The Deck department is concerned with the overall operation of the ship. Responsibilities include navigation, communications, cargo and other ship operations, stability and safety.

The Engineering department is responsible for all technical services including main engine propulsion, other plant and machinery, electrical generation and maintenance, all controlled by a complex array of computer control systems that need monitoring 24 hours a day. Electro-Technical specialists manage control systems in some vessels.

The number in a ship’s crew varies according to the size and type of vessel and its area of operation. The ship’s company may range from as few as six crew members up to twenty-five or more. These numbers will be significantly higher on passenger ships and ferries in all departments but particularly in the Hotel Services department, depending on the number of passengers carried.