Abstract: A cardio-thoracic compression harness that includes a pair of bands are placed around the body of the user so as to compress and hold in place the thorax, sternum, and ribs. The device is positioned so that the bands contact the user's body above and below the breasts. This allows a female user to wear the device while wearing a bra. The device can also be constructed as a device integral to an undergarment such as a bra. The device includes a plurality of closures so that it can conform easily to the shape of the user's body. The device may also include shoulder straps for more secure positioning. The harness can be worn under or over the user's clothing.