A flexible but strong universal die is disclosed, that is flexible enough to be elastically deflected into different curvatures by actuating forces and moments, while being strong enough to support the die forces and moments that it has to apply to parts to form them to the shape corresponding to its shape. A design of the die and actuation locations that makes it easy to deflect it into different constant curvatures, as well as into shapes with gradients of curvature along the length of the die, and the use of these dies for stretch roll forming are disclosed.