The vertebrate axial musculoskeletal system arises from distinct somitic compartments: the axial skeleton develops from the sclerotome, the skeletal muscle from the myotome and the axial tendons from a region of the sclerotome close to the myotome, called the syndetome, which is defined by expression of the gene scleraxis (Scx). On p. 3885, Brent and Tabin determine the molecular mechanisms responsible for positioning the syndetome. The group has shown before that FGF signalling from the myotome is necessary and sufficient for Scx expression. Here, the researchers report that two transcriptional targets and effectors of FGF signalling– Pea3 and Erm – are required for FGF-mediated induction of Scx. They propose a model for tendon development in which FGFs from the myotome activate Pea3 and Erm expression in the sclerotome. Further FGF signalling then activates Pea3 and Erm, which directly or indirectly trigger the transcription of Scx.