- 75 made university students responded to newspaper asking for volunteers for prison study paying $15 per day
- 24 students rated most physically + mentally were chosen
- basement of Stanford university was converted into mock prison
- prisoners arrested from their homes without knowledge by county police
- when arrive they were stripped + deloused
- prisoners given smock, number, ball + chain
- guards wore khaki uniform, reflective sunglasses, baton + whistle
- guards + prison randomly assigned to roles