Lipid membranes form the boundaries of all living cells, and many internal organelles in nucleated cells. They are molecularly thin fluid elastic films with amazing material properties that underly their biological function, many of which pose unanswered biophysical and biological questions to this day. Why are there so many different types of lipids? How do proteins insert into, bind onto, and fold inside membranes? How do cell membranes maintain their asymmetry? How do elastic properties emerge from their self-assembled components? How are stresses transmitted along membranes? – Our team has many years of experience in studying lipid membranes using experiment, theory, and computation. Using diffuse X-ray scattering, neutron reflectometry, densitometry, surface plasmon resonance, molecular dynamics simulation, systematic coarse-graining, continuum theory, differential geometry, and statistical field theory we apply a wide set of tools to learn more about the thin films that separate life from death.