A system for the medical-therapeutic treatment of a target object in a patient who is located on a treatment table surface, with - a freehand ultrasonic probe which is spatially positionable and alignable by the user of the system in a manual manner within a locating region in the reference system (l 1) of the treatment table surface, - a therapy source which is alignable onto the target object in at least two angle planes in the reference system of the treatment table surface, - a therapy source ultrasonic probe which is positioned or positionable onto a fixed position in the reference system (I') of the therapy source and whose alignment in this position is fixed in the two angle planes in the reference system (I') of the therapy source, - a locating system for detecting the spatial position and alignment of the freehand ultrasonic probe within the locating region in the reference system (l 1) of the treatment table surface, wherein the locating system is designed to store six coordinates for a spatial position and alignment of the freehand ultrasonic probe with a viewing direction onto the target object, said position and alignment being selected by the user, and wherein the therapy source is designed to be aligned onto the target object in the reference system (l 1) of the treatment table surface on the basis of the stored six coordinates in the at least two angle planes, such that the therapy source ultrasonic probe in the reference system (l 1) of the treatment table surface essentially has the same viewing direction onto the target object as the freehand ultrasonic probe at the point in time of the storing of the six coordinates. - a freehand ultrasonic probe which is spatially positionable and alignable by the user of the system in a manual manner within a locating region in the reference system (l 1) of the treatment table surface, - a therapy source which is alignable onto the target object in at least two angle planes in the reference system of the treatment table surface, - a therapy source ultrasonic probe which is positioned or positionable onto a fixed position in the reference system (I') of the therapy source and whose alignment in this position is fixed in the two angle planes in the reference system (I') of the therapy source, - a locating system for detecting the spatial position and alignment of the freehand ultrasonic probe within the locating region in the reference system (l 1) of the treatment table surface, wherein the locating system is designed to store six coordinates for a spatial position and alignment of the freehand ultrasonic probe with a viewing direction onto the target object, said position and alignment being selected by the user, and wherein the therapy source is designed to be aligned onto the target object in the reference system (l 1) of the treatment table surface on the basis of the stored six coordinates in the at least two angle planes, such that the therapy source ultrasonic probe in the reference system (l 1) of the treatment table surface essentially has the same viewing direction onto the target object as the freehand ultrasonic probe at the point in time of the storing of the six coordinates.