A device for determining the position and/or orientation of a creature (3) relative to an environment, comprising a locating member (4) connected to the creature (3), the locating member including a transducer (5) arranged to determine its position and/or orientation relative to the environment by receiving incident signals from signal sources (9) in the environment and record the relative incident directions of the signals received in relation to the transducer, and an element (8) by which the creature (3) and the transducer (5) are connected to each other, so that the relative positions and/or orientations of the creature (3) and the transducer (5) are arranged to be within a limited interval, for determining the position and/or orientation of the creature (3) by the information about the position and/or orientation of the transducer (5).