Abstract: A clamp is disclosed for joining fiberglass reinforced plastic grid members in order to provide a corrosive-resistant frame work for a suspended ceiling. The grid members are of an inverted T configuration. The flanges of the cross members are cut back so that the web of each cross member rests on the flange of a support member with the flanges of the support and cross members flush. The keepers of an integrally formed stainless steel clamp extend through holes in the web of the support member on either side of the web of the cross member. The legs of the clamp straddle the web of the cross member and a cross piece of the clamp is received in a notch in the top of the web. In this position the clamp is stressed and so provides a force holding the cross member on the flange of the support member.