The interplay between proteins and membrane lipids is central to almost every aspect of cell biology. This laboratory is interested in fundamental questions of how the interactions between proteins and membranes determine cell and organelle shape and the evolution of shape over time, how protein-membrane interactions turn on and off the signals that control essential cell processes, and how pathogens such as HIV-1 subvert and co-opt these interactions. The roots of our research program are in the power of x-ray crystallography to reveal the structures of membrane-interacting proteins at high resolution, leading to insights in the physical basis of protein-membrane interactions. Crystallography continues to be at the heart of our research because of its unequaled power to reveal the shape of proteins and the atomic basis for protein-protein and protein-lipid interactions. The reconstitution of membrane remodeling pathways in synthetic membrane systems has taken on equal importance in the lab. These core approaches are complemented by studies in solution or on membranes by hydrodynamic, small angle x-ray scattering, fluorescence imaging, and electron microscopy.