Abstract: An apparatus for joining together two enclosures which both mechanically fastens the enclosures and provides shielding against electromagnetic emissions. A tubular electromagnetic shield formed as an endless loop is secured around the perimeter of an interface opening by a plurality of shield fasteners. At least some fasteners are of a fold-over type which encircles a portion of the shield and secures it to a surface. The apparatus includes fastener/spacer assemblies for joining the enclosures such that they exert a compressive force on the shield which is disposed between them.