Cover picture: The lung surfactant monolayer at the air-water interface coexists with bilayer folds in water. The folds are formed upon collapse of monolayer induced by lateral compression. The simulation setup includes a water slab bounded by two monolayers. Circular and rectangular bilayer folds are attached to the top and bottom monolayers, respectively. DPPC lipids are shown in green, POPG lipids in yellow, cholesterol in cyan, surfactant protein C (SP-C) in red, water in blue, and Na⁺ ions in gray. Lipid headgroups are represented as spheres; lipid chains, cholesterol, and SP-C as sticks; the size of several selected lipid molecules is increased to show their conformation. See the article by Baoukina et al. on page 3775.