Cover legend: This scanning electron micrograph shows a single oligodendrocyte initiating ensheathment of a micropillar on the BIMA (Binary Indicant of myelination using Micropillar Arrays) screening platform. The cell soma and membrane are pseudocolored green to illustrate the extensive and elaborate branching. Image by Michael Devereux and Jonah R. Chan. For more information, see the article by Mei et al. (pages 7925–7935).