Aim - To investigate how freely people would conform to the roles as a guard and prisoner in a role playing exercise that recreated prison life.
Sample - 24 emotionally stable US male university students
Procedure - randomly allocated to prisoner or guard
Prisoners - arrested at their homes, taken to prison, searched and dressed in smock uniforms - given numbers
Guards - given uniform, mirrored glasses, keep prisoners under control but use no physical violence - created a loss of personal identity
Zimbardo acted as a prison officer