Abstract: Steering and manoeuvering system for water-borne vessels with two individually turnable propulsion units aranged mutually spaced athwartships in the stern portion of the vessel, and including an actuating turning device (7,8) actuable by a steering control (1), e.g. a lever, such as to maintain the propulsing units parallel during turning in normal sailing of the vehicle ahead or astern, i.e. in the so-called normal steering mode, and an actuating drive device (9,10) for setting the propulsive power and direction ahead/astern of the respective propulsion unit, said drive device being actuable by a power control (2). The system is switchable between said normal steering mode (3) and at least one special manoeuvering mode (4,5), in which the two propulsion units achieve a force resultant directed substantially athwartships for athwartships and/or turning movement of the vessel.