Recent maritime disaster of a large tanker often causes a serious oil pollution. To prevent such disaster, some kind of manoeuvring standard has been demanded over the world. International Maritime Organization (IMO) has been working out to settle the standard in these several years. As the result, the interim standards for ship manoeuvrability (A. 751) was adopted in November 1993. It is applied to the ships of 100 m in length and over, and every chemical tankers and gas carriers, which are constructed on or after 1 July 1994. This interim standards cover turning ability, initial turning ability, stopping ability and course-keeping/changing ability. The criterion of stopping ability is defined that the track reach in the full astern stopping test should not exceed 15 ship lengths. Ship designers should evaluate this stopping distance in early design stage. In this paper simple mathematical models for predicting stopping distance and time are presented, and these models are confirmed by a number of full-scale trial results. Then, it has been clarified that the non-dimensional stopping distance and time are almost proportional to (displacement of ship/main engine horse power) and the square of initial ship's speed. Through this research, it is also pointed out that the stopping distances of many VLCCs have already exceeded the above limit. This criterion becomes very severe particularly for such large ships. Since the application of the standard for stopping distance regulates the minimu required horse power simultaneously, the author would like to emphasis for the criteria to be re-examined and finalized under the world-wide agreements.