Sub-sea manipulators in use today are not capable to perform all des- ired work tasks needed in underwater intervention operations. Especi- ally in deep sea operations manipulator systems have to comply with complex work tasks without any help of human divers. To meet this challenge a new manipulator with high accuracy and repeatability for sub-sea tasks is being developed. The manipulator consists of 6 hydr- aulically driven joints where each joint consists of a hydraulic pre- cision motor, a servo valve, a harmonic drive gear unit and a resolv- er for position feedback. The communication between robot and operat- or is carried out in a PC-based control system with a graphical inte- rface. The importance of designing and implementation of the high pe- rformance manipulator is emphasised. This paper presents the design considerations and optimisation of both mechanical and fluid power elements in the HIPRUM project.