The regional distribution of cholecystokinin-like immunoreactivity (CCK-LI) in postmortem human brain material has been investigated. CCK-LI was concentrated particularly in the forebrain (all cerebral cortical areas, amygdala, and hippocampus), with smaller amounts in the basal ganglia, hypothalamus, and periventricular grey. Lowest amounts of CCK-LI were found in the thalamus, cerebellum, and spinal cord.