Abstract: A stool having a base and a seat relatively adjustable to the base by a plurality of vertical cylindrical telescoping sections supporting the seat and fixed to the base. Radial retaining lugs fixed to telescoping rods housed within the cylindrical telescoping sections are received within slots in the sidewalls of the telescoping sections to lock the seat in adjusted position. The lugs are biassed by a coil spring between the rods into the slots. The spring is compressed to remove the lugs from the slots to readjust the height of the seat relative to the base.