Cover legend: Confocal image of a fluorescently labeled tissue section prepared from an embryonic day 13.5 mouse brain. Most migratory interneurons in the developing cerebral cortex express GFP (green) and calbindin (red). Nuclei are counterstained with Draq5 (purple). The accompanying cover video shows the robust migration of cortical interneurons into the developing mouse cerebral cortex. For more information, see the article by Myers et al. in the June 4 issue (pages 7787–7801). http://link.brightcove.com/services/player/bcpid2666468392001?bckey=AQ~~,AAACbMgRO0E~,_GTnRyY88ZaY6C28AhYF8orFcgnUlqsq&bctid=3596600168001