Abstract: An adjustable clamp for holding a workpiece wherein the clamp is characterized by a pair of fixed, opposing jaws and a first clamping member movably disposed on one of said jaws. The adjustable clamp further comprises a second clamping member movably attached to a clamp positioning bar formed on the body of the adjustable clamp whereby the second clamping member may be selectively positioned in first and second clamping positions with respect to a normal plane between the jaws. A second embodiment for the adjustable clamp is disclosed comprising a third clamping member operatively mounted on the other jaw in substantially opposing relation to the first clamping member, whereby a workpiece may be centered between the two jaws.