Cover image: Composite image of cells in a macroporous hydrogel. (Left) Tubule of platelet endothelial cell adhesion molecule (PECAM)-positive endothelial cells. (Center) Coculture of PECAM-positive endothelial cells (red) with neural progenitors (green). (Right) Neural progenitor cells at 5 days after seeding. See the article by Ford et al. on pages 2512–2517. Images courtesy of Millicent Ford.