Access to the article is free, however registration and sign-in are required. How do cells make vesicles, a process that requires the bending of membranes? In their Perspective, Lee and Schekman discuss new findings (Peter et al.) that identify a domain called the BAR domain in proteins, such as amphiphysin and endophilin, that induces the curvature of membranes at different points during vesicle formation.