Abstract: A protective helmet has a fitting and retention system which allows for fing a variety of head sizes and shapes with a single helmet size and also allows for precision reproducible fitting for a repeat user. The protective helmet has an energy-attenuating liner comprising a brow pad, a crown pad and a floating occipital pusher plate. The pusher plate hangs from the rear of the helmet on adjustable straps which are tensioned to urge the wearer's head forward toward the front of the helmet. This ensures that weapon sighting/designation systems are consistently aligned each time the helmet is worn. This feature also allows the helmet to accommodate a variety of head sizes and shapes. Pusher plate movement is preferably controlled using a parallel arrangement of two horizontal straps in which the lower strap is adjusted as part of the chinstrap assembly while the upper strap routed through a slot in the helmet shell and coupled to a device which simultaneously tensions the pusher plate and the ear cups.