Despite the important roles they play in cell membrane structure and function, lipid assemblies remain poorly characterized from a molecular perspective. Whether lipids mix or phase segregate and on what length scales, how membrane composition confers macroscopic properties such as membrane flexibility, curvature and permeability, and how membranes maintain asymmetric distributions of lipids across the bilayer are all questions that relate directly to how lipid assemblies sustain cellular integrity. This workshop will bring together leading investigators to discuss recent experimental and theoretical advances and identify pressing challenges in the field of lipid membrane chemistry and physics.