Method for determining the pose of an object, preferably of a medical device, the method comprising the following steps: a) providing an object, preferably a medical device, comprising at least one visual identification element (4a, 4b, 4c) and an orientation sensor for determining an absolute orientation and/or angular velocity of the object; b) providing at least two cameras (7a, 7b) adapted to visually track the at least one visual identification element, each camera having a field of view and remaining stationary during the method, the cameras defining a camera coordinate system; c) acquiring image data of the field of view of the at least two cameras while the object is being moved; d) acquiring orientation data provided by the orientation sensor while the object is being moved; e) calibrating the orientation sensor with respect to the camera coordinate system; and f) analyzing the image data and the orientation data to determine the pose of the object during its movement; wherein: f1) the orientation of the object is determined on the basis of the orientation data and/or the image data when at least a portion of the visual identification element is sufficiently visible to both cameras to allow for determining the orientation of the object; f2) the orientation of the object is determined on the basis of the orientation data alone when the visual identification element is not sufficiently visible to both cameras to allow for determining the orientation of the object; f3) the position of the object is determined on the basis of the image data alone when at least a portion of the visual identification element is sufficiently visible to both cameras to allow for determining the position of the object; and f4) the position of the object is determined on the basis of a combination of the image data and the orientation data determined according to step f1) or f2) when at least a portion of the visual identification element is sufficiently visible to both cameras to allow for identifying said portion and for determining the position of said portion. a) providing an object, preferably a medical device, comprising at least one visual identification element (4a, 4b, 4c) and an orientation sensor for determining an absolute orientation and/or angular velocity of the object; b) providing at least two cameras (7a, 7b) adapted to visually track the at least one visual identification element, each camera having a field of view and remaining stationary during the method, the cameras defining a camera coordinate system; c) acquiring image data of the field of view of the at least two cameras while the object is being moved; d) acquiring orientation data provided by the orientation sensor while the object is being moved; e) calibrating the orientation sensor with respect to the camera coordinate system; and f) analyzing the image data and the orientation data to determine the pose of the object during its movement; wherein: f1) the orientation of the object is determined on the basis of the orientation data and/or the image data when at least a portion of the visual identification element is sufficiently visible to both cameras to allow for determining the orientation of the object; f2) the orientation of the object is determined on the basis of the orientation data alone when the visual identification element is not sufficiently visible to both cameras to allow for determining the orientation of the object; f3) the position of the object is determined on the basis of the image data alone when at least a portion of the visual identification element is sufficiently visible to both cameras to allow for determining the position of the object; and f4) the position of the object is determined on the basis of a combination of the image data and the orientation data determined according to step f1) or f2) when at least a portion of the visual identification element is sufficiently visible to both cameras to allow for identifying said portion and for determining the position of said portion. f1) the orientation of the object is determined on the basis of the orientation data and/or the image data when at least a portion of the visual identification element is sufficiently visible to both cameras to allow for determining the orientation of the object; f2) the orientation of the object is determined on the basis of the orientation data alone when the visual identification element is not sufficiently visible to both cameras to allow for determining the orientation of the object; f3) the position of the object is determined on the basis of the image data alone when at least a portion of the visual identification element is sufficiently visible to both cameras to allow for determining the position of the object; and f4) the position of the object is determined on the basis of a combination of the image data and the orientation data determined according to step f1) or f2) when at least a portion of the visual identification element is sufficiently visible to both cameras to allow for identifying said portion and for determining the position of said portion.