A patient positioning assembly for adjusting patient position during a therapeutic radiation treatment using a therapeutic radiation treatment system, said therapeutic radiation treatment system including a therapeutic radiation source for generating at least one therapeutic radiation beam, and an image system for generating image data representative of at least one image of a treatment target, said image data containing information regarding the near real time position of said treatment target with respect to a treatment coordinate system, wherein said patient positioning assembly comprises: a robotic positioning device for supporting and moving the patient loaded on said robotic positioning device, wherein said robotic positioning device is capable of moving said patient in at least five degrees of freedom, wherein said robotic positioning device comprises; a treatment table to support said patient thereon; an arm assembly which is coupled to the treatment table and configured to rotate the treatment table about roll-, pitch-, and yaw-axes for three rotational degrees of freedom and to translate the treatment table in three translational degrees of freedom; and a sensor system adapted to detect the position of said robotic positioning device relative to said treatment coordinate system, and a controller operatively connected with said sensor system and adapted to receive position data of said robotic positioning device, and operatively connected to said therapeutic radiation treatment system and adapted to receive near real time image data of said treatment target and information representative of the position of said therapeutic radiation source, wherein said controller is operatively connected to said robotic positioning device and is adapted to control the movement of said robotic positioning device to align said treatment target with said therapeutic radiation source. a robotic positioning device for supporting and moving the patient loaded on said robotic positioning device, wherein said robotic positioning device is capable of moving said patient in at least five degrees of freedom, wherein said robotic positioning device comprises; a treatment table to support said patient thereon; an arm assembly which is coupled to the treatment table and configured to rotate the treatment table about roll-, pitch-, and yaw-axes for three rotational degrees of freedom and to translate the treatment table in three translational degrees of freedom; and a sensor system adapted to detect the position of said robotic positioning device relative to said treatment coordinate system, and a controller operatively connected with said sensor system and adapted to receive position data of said robotic positioning device, and operatively connected to said therapeutic radiation treatment system and adapted to receive near real time image data of said treatment target and information representative of the position of said therapeutic radiation source, wherein said controller is operatively connected to said robotic positioning device and is adapted to control the movement of said robotic positioning device to align said treatment target with said therapeutic radiation source.