Rats injected intracerebroventricularly with corticotropin releasing factor (CRF) at the level of the lateral ventricle or cisterna magna showed a dose-dependent increase in locomotor activity. The increase in locomotor activity from injections of CRF into the cisterna magna was blocked by a cold cream plug in the cerebral aqueduct. An identical plug failed to block the increase in locomotor activity produced by CRF injected into the lateral ventricle. Intracerebral injections of CRF produced a site specific increase in locomotor activity with the largest increases observed from CRF injected into the substantia innominata/lateral preoptic area. Results suggest that the locomotor activating effects of CRF may be due to an activation of CRF receptors in the ventral forebrain, a region rich in CRF cell bodies and projections.