(How diesel-electric system improves reliability, operational flexibility and economy of the survey vessel IMOR) IMOR was built for Maritime Institute of Gdansk as a multi -purpose shallow water survey and ROV support twin-hull vessel. It is configured and capable of performing a range of tasks, such as: hydrographic and geophysical operations, bottom and pipeline inspection, etc. Its small size, small draught, relatively high power and great flexibility of possible applications makes it ideal for work on shallow waters and offshore projects starting onshore. It is equipped with diesel-electric propulsion system that consists of: 3 generator sets, 2 dual azipod aft active rudders - propellers, 2 dual waterjet bow thrusters. These units are powered by electric motors controlled by helmsman stand and DP system. First year of service has proven the project success. In contrast to conventional construction, both fuel consumption and pollution discharges have been reduced substantially. Additionally, manoeuvring and maintenance of the vessel has been improved. A great advantage of such system is the use of sufficient number of auxiliary diesel engines; consequently operation of all engines at a time is avoided. During idle operation or reduced speed of the vessel, it is sufficient to connect only one or two auxiliary generators which, in return, will be operated at an optimum capacity and efficiency. On demand, high speed and operation of all vessel auxiliary generators can be achieved in a few seconds. This flexibility enables substantial energy-savings and exploitation cost advantages. Other benefits may be summarized as follows: high survivability, reduction of noise and vibration, improved operational flexibility and reliability, increased flexibility and adaptability for different kind of survey works, increased space available, reduced manning and logistics.