The invention concerns a method of mutually aligning bodies, in particular for the parallel alignment of shafts, rollers and the like, which can be carried out economically and simply in a substantially shorter time than the known methods used for this purpose. The essence of the invention is the use of an optical gyroscope, for example a fiber-optic gyroscope (
), in a position-measuring sensor (
) which is placed in turn in a specific position on the bodies (
1, 2, 3
) to be mutually aligned for a given time interval to measure the relative angular position. The position-measuring sensor (
) supplies angle data on the basis of which it can be established whether, and if necessary which, position corrections have to be made at the bodies in order to bring them into the desired state of alignment. The invention further concerns a position-measuring sensor which can be used in the method according to the invention.