Abstract: A collar shaping device having a U-shaped body adapted to be positioned under the collar of a shirt. The U-shaped body defines a central portion and first and second legs extending therefrom and undulates in a vertical direction. The central portion defines an upper rear contact region that engages the underside of the collar at the midpoint of the central portion. The first and second legs each have a proximate region connected with the central portion and a freely extending distal region. The proximate regions of the first and second legs defines a lower contact region that engages the upper shoulder area of shirt body while the distal regions of the first and second legs defines an upper forward contact region that engages the underside of the collar proximate the forward ends of the collar. Shirt assemblies and methods employing such devices are also disclosed.