Our objective is to evaluate magnetic resonance spectroscopy's potential, 239Pu nuclear magnetic resonance (NMR) in particular, as a probe for plutonium-containing materials. As a key constituent of both nuclear fuels and nuclear weapons, plutonium has a pervasive presence in the Department of Energy's core missions in energy production, national security, waste management, and environmental remediation. Plutonium's position in the middle of the actinide (5f) series of elements endows it with extraordinarily rich chemical and physical properties that make it a compelling subject for DOE's basic research mission as well. But despite the need for advanced tools to probe this formidably complex element, the progress of plutonium science has been severely constrained by the inability to perform NMR spectroscopic experiments, which, as exemplified by NMR studies of other metallic elements, offer great promise for elucidating key features of electronic structure in the vicinity of Pu centers. Only two laboratories in the world have demonstrated an existing capability to perform magic angle spinning NMR measurements on plutonium-containing solids, but only PNNL is effectively available to American researchers for this work.