mock prison in the basement of Stanford Uni
24 US male student volunteers
psychological assessment done before to choose psychologically healthy participants
agreed to participate for 7-14 days
paid $15 a day
randomly assigned the role of prisoner or guard
prisoners unexpectantly arrested at home
prisoners deloused, given prison uniform and ID number
guards were given uniforms, clubs, whistles and reflective sunglasses
guards were told to run prison but NOT harm prisoners