How vitamins and growth factors interact during fetal development to form the body plan is complex and poorly understood, but is relevant to understanding birth defects and to developing regenerative therapies. This paper shows how vitamin A (retinoic acid) orchestrates signaling from fibroblast growth factor to control the development of the mesodermal lineages that form the skeleton and skeletal musculature, and coordinates development of these structures to keep it in sync with the developing nervous system.