Current models of hypothalamic function cannot account for the rapid induction of satiety: activation of arcuate nucleus pro-opiomelanocortin (POMC)-expressing neurons (ARCPOMC neurons) only reduces hunger after several hours. The authors showed that manipulation of a population of glutamatergic ARC neurons rapidly alters feeding in mice through a projection to the paraventricular hypothalamus, where their inputs converge with those of ARCPOMC neurons and agouti-related protein-expressing ARC neurons to mediate their effects.