Sleep is a deeply conserved phenomenon, yet the mechanisms that regulate sleep are still being uncovered. Over the past decade, we have leveraged the genetic facility and optical transparency of the larval zebrafish to map molecular and neuronal substrates that control the timing and duration of sleep. Like humans, zebrafish display circadian and homeostatically regulated periods of quiescence, during which the larvae are less sensitive to their environment. Furthermore, zebrafish sleep is regulated by similar genetic and neuronal systems as humans, including the hypocretin/orexin system that is lost in patients with the sleep disease, narcolepsy. Using a combination of pharmacology, genetics, and neuronal imaging, we have uncovered several additional neuropeptide signaling systems that modulate sleep’s timing relative to the light-dark cycle and duration after prolonged wakefulness. This presentation will focus on our recent work that aim to address how these neuropeptides impact neuronal circuits to orchestrate sleep drive.