Our research investigates how the physical forces of nature drive a simple string of amino acids into a stable, conformationally defined protein - in the lipid membrane. For soluble proteins, the burial of hydrophobic groups away from aqueous interfaces is a major driving force, but membrane-embedded proteins cannot experience hydrophobic forces, as the lipid bilayer lacks water. A fundamental conundrum thus arises: how does a greasy protein surface find its greasy protein partner in the greasy lipid bilayer to fold faithfully into its native structure? In our lab, we measure the energetics of membrane protein assembly, in lipid bilayers, using the homodimeric Cl-/H+ antiporter CLC- ec1 as a model system. We approach this curious question with a variety of experimental techniques including membrane protein purification and functional reconstitution, electrophysiology, x-ray crystallography, single-molecule TIRF microscopy and computational modeling.