Abstract: A sitting device that gives the user an option to sit with a lower portion of the body supported by a half seat, while maintaining a standing posture with the unsupported leg. The sitting device includes two, left and right, half seats and a foot stool. The device also includes a seat support frame and two half-seat-position-adjusting actuators. The frame includes a horizontal crossbar and a vertical guide tube, wherein the back end of each of the two half seats is pivotally secured on the horizontal bar. The vertical guide tube houses a length-changing mechanism to vary the height of the sitting device and a height fixing mechanism which prevents yielding of the height of the sitting device when the user sits. Also comprising are the two half-seat-position-adjusting actuators attached at one end of each to the vertical tube and at the other end to the respective half seat.