Abstract: An adjustable workpiece holder has at least one jaw member holding a plurality of finger elements lengthwise in parallel therein. The finger elements have side surfaces with serrations formed over a given length thereof. The serrations allow the finger elements to be selectively adjustable in lengthwise position relative to adjacent finger elements, so that they can conform to the contour of the workpiece. The finger elements may have a total width that fits snugly within a recess or pocket of the jaw member. A releasable clamp applies firm lateral pressure to the finger elements to prevent any slippage. The jaw member may be part of a machining assembly or retrofitted to one or both sides of a standard milling or drill press vise. It may also be adapted for use in forming, stamping, bending, or shaping material, or for profiling or as a template for holding or positioning workpieces in other applications.