With the MST facility, physicists study hot plasmas that are relevant to fusion energy research, with links to plasma astrophysics. They work toward three coupled goals: to advance the magnetic configuration known as the reversed field pinch as a potential fusion energy source, to investigate specific fusion energy science issues that are of general application to fusion energy research, and to explore plasma phenomena that have physics connections to plasma processes in the cosmos. This rather broad mission is feasible since all three aims are linked through common physics problems. The mission is also reflected in the funding support for MST, which is provided by the Department of Energy (Office of Fusion Energy Sciences) and the National Science Foundation through the Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas.