Abstract: A waterjet propulsion apparatus comprising a motor, an impeller driven by the motor via a drive shaft, and a power source. A fluid flow-path is formed through the apparatus, the flow-path extending from at least one fluid inlet, through two propulsion passages, each propulsion passage extending from a propulsion inlet to an outlet located at a rear end of the apparatus. The impeller is located within the flow-path, after the at least one fluid inlet, and before the propulsion inlet of the each of the propulsion passages. The motor is located outside of the flow-path, between the two propulsion passages, and behind the impeller. The apparatus is advantageous in that it provides a compact and lightweight construction that can, for example, be used as part of a personal marine propulsion device that can be used by an individual.