A universally fitting headgear that is readily adjustable to a variety of different sized patients and that couples a patient interface device to an airway of the patient. The headgear includes a headpiece that fits on the user's heal in a cap-like fashion. The circumference of the headpiece is adjustable so that a single sized headgear can be fit to a number of different sized patient's. The headpiece includes adjustment straps which adjustably connect to each other on the sides of the patient's head. The headpiece further includes connecting straps to adjustably connecting the headgear to a patient interface device, such as a gas delivery mask. The headgear of the present invention fits a wide range of head sizes and shapes, is easy to use, and provides increased stability.