Cerebrospinal fluid of the major central metabolites of serotonin (5HT), norepinephrine (NE), and dopamine (DA)--5-hydroxyindoleacetic acid (5HIAA), 3-methoxy-4-hydroxy=phenylglycol (MHPG), and homovanillic acid (HVA), respectively--were studied in a group of 26 age-similar military men with no history of major psychiatric illness, but with various personality disorders and difficulties adjusting to military life. Independently scored history of aggressive behavior showed a significant negative correlation with 5HIAA (r = -0.78) and a significant positive correlation with MHPG (r = 0.64).