Tinderbox homicides, which include a substantial preponderance of homicides committed every year, occur between people known to each other and who share many similar characteristics, and involve long-standing or emerging disputes; in many cases, the outcome in terms of which party becomes the victim is determined only by chance. This chapter reviews the evidence suggesting that neurologic dysfunction underlies impulsivity and leads in many cases to tinderbox violence. There is also evidence to indicate that people with a high taste for risk, which itself implies the presence of neurogenic impulsivity, may purposely put themselves in contact with psychosocial situations and peers that will create the proximate opportunity for criminal violence. This discussion raises the issue of whether persons susceptible to neurogenic violence can be held criminally culpable for their actions. 1 figure, 6 notes, and 116 references