The formation of precise neuronal connections is essential for brain function. During development, neurons extend axons that are guided toward their synaptic targets by guidance factors present in their environment. Concomitantly or subsequently to this guidance process, refinement mechanisms correct axons that have deviated from the right path, thereby ensuring the formation of accurate neuronal circuits. Although the elimination of axonal projections is a selective process, how it is initiated and controlled in vivo remains unclear. In their latest study titled "Teneurin trans-axonal signaling prunes topographically missorted axons", members of the Poulain lab reveal that trans-axonal signaling mediated by the cell surface molecules Glypican-3, Teneurin-3, and Latrophilin-3 prunes misrouted retinal axons in the visual system. These findings show an essential function for Glypican-3, Teneurin-3, and Latrophilin-3 in topographic tract organization and demonstrate that axonal pruning can be initiated by signaling among axons themselves. Congrats!