This document provides a brief summary of the capabilities of the Multi-Axial Subassemblage Testing (MAST) System at the University of Minnesota. The MAST system is one of the large-scale testing facilities awarded under the George E. Brown, Jr. Network for Earthquake Engineering Simulation program, funded through the National Science Foundation. The MAST system enables multi-axial cyclic static tests of large-scale structural subassemblages including portions of beam-column frame systems, walls, and bridge piers. The MAST system concept, employing a six-degree-of-freedom controller, can be used to apply realistic states of deformations and loading in a straightforward and reproducible manner. The MAST system advances the current state of technology by allowing the experimental simulation of complex boundary effects through its multi-axial capabilities, which can impose multiple-degree-of-freedom states of deformation and load. The system is unique in size and scope and will greatly expand the large-scale earthquake experimentation capabilities both nationally and internationally.