A Compact Torus (CT) is a low-aspect-ratio, axisymmetric, closed-magnetic-field-line configuration with no vessel wall or magnetic field coils linking the hole in the plasma toroid. The potential reactor advantages of such devices are:— simple vacuum vessel, coil and blanket geometry;— high engineering beta values;— compact, high-power-density reactor cores;— possible translation of plasma toroid (allowing the formation chamber to be physically separated from the burn chamber with its high neutron wall loading).