The invention relates to a semiconductor structures and methods of manufacture and, more particularly, to a dual contact trench resistor in shallow trench isolation (STI) and methods of manufacture. In a first aspect of the invention, a method comprises forming a trench in a substrate; forming a first insulator layer within the trench; forming a first electrode within the trench, on the first insulator layer, and isolated from the substrate by the first insulator layer; forming a second insulator layer within the trench and on the first electrode; and forming a second electrode within the trench, on the second insulator layer, and isolated from the substrate by the first insulator layer and the second insulator layer.