The Madison Symmetric Torus (MST) is the newest and largest reversed-field pinch (RFP) currently in operation. It incorporates a number of design features that set it apart from other pinches, including the use of the conducting shell as both a vacuum vessel and single-turn toroidal field coil. Specially insulated voltage gaps are exposed to the plasma. Magnetic field errors at these gaps as well as at the various diagnostic and pumping ports are minimized through a variety of techniques. The physics goals of MST include study of the effect of large plasma size on confinement and the detailed investigation of RFP turbulence, dynamo, and transport. Details of the design and initial operation of the device are presented.