Abstract: A portable hip abduction apparatus for improving the posture and torso stability of a seated user, especially an individual with cerebral palsy. A flexible sheet is provided for placement on a seating surface. A backrest of the seating section and/or an incline block may be used to gradually elevate a seating section of the flexible sheet located adjacent a pommel attachment section. Along the pommel attachment section of the flexible sheet, a preferably trapezoidal abduction pommel is releasably connected. Due to the incline produced by either the incline block and/or the backrest, a user seated on the seating surface is urged towards the abduction pommel to wedge the user therebetween. In this manner, the wedging action causes the user's legs and hips to be abducted and the user's pelvis to be rotated forward toward vertical.