Initial studies revealed essential roles for Alk signaling in visceral muscle founder cell specification in the fly [6, 8] and the sensory control of dauer formation in C. elegans [11] while aberrant ALK signaling in humans was identified as oncogenic driver and primarily studied in the context of anaplastic large cell lymphoma, neuroblastoma, and non-small cell lung-cancer [14–16]. The gene discussed is ALK; the disease is anaplastic large cell lymphoma.