A face mask assembly for supplying breathable gas to a wearer, said face mask assembly comprising: a mask frame (1512) including a support, a facial cushion (16) attached to the mask frame, and a forehead support (101), said forehead support including a forehead cushion assembly (1551, 1552) and an adjustment knob (1550) operatively coupled to the forehead cushion assembly wherein the forehead cushion assembly is generally linearly moved between retracted and extended positions in a direction towards and away from a patients forehead with respect to the support.