Eukaryotic cells are compartmentalized into distinct membrane-bound organelles and vesicular structures, each with its own characteristic function and set of protein constituents. Work in my laboratory is focused on understanding how integral membrane protein complexes are assembled and sorted to the appropriate compartments within the late secretory and endocytic pathways, how sorting and assembly contribute to the biogenesis of cell type-specific organelles, how these processes impact biological function in the pigmentary, blood clotting, and immune systems, and how they are thwarted by generally rare genetic diseases.