Methods and systems for relating anatomical patient information between different medical machines in a radiation therapy or diagnostic process are disclosed. In connection with each machine a respective 2- or 3-dimensional representation of at least a portion of the patient is determined in relation to an overall common coordinate system associated with the patient. The anatomical patient information between the different medical machines are then related based on the 2- or 3-dimensional representations as common reference between the machines. This makes it possible to integrate and depict anatomical information obtained with different imaging techniques into the common coordinate system. Also methods and systems for accurate patient positioning are disclosed, whereby the 2- or 3- dimensional representation is compared to a reference representation. The patient is then positioned to minimize the deviation between the representations.