Robert Behringer works in granular materials, fluids and statistical mechanics. His Ph.D. probed the liquid-gas critical point of liquid helium. His post-doctoral work used the special properties of liquid helium to probe Rayleigh-Benard convection as well as properties of the superfluid helium. As an assistant professor at Wesleyan University (Middletown, CT), he carried out studies of convection as well as heat and mass transport. Since 1982, he has been at Duke University, where he has studied granular materials, convection, flow in porous media, and quantum fluids. He was among a small group of researchers who brought research on granular materials into the physics domain. He has studied flows and instabilities in granular materials. His recent work has exploited photoelastic and laser sheet scanning techniques to probe the properties of granular systems near jamming. He and his collaborators have shown that frictional granular materials have a rich jamming phase diagram that was not previously expected. This discovery shows that frictional granular materials jam under shear at densities that are substantially lower than random dense packings. This discovery is likely to be highly relevant to industrial applications.