This chapter examines the difficult and complex role of the regulator in limiting the occurrence of organizational accidents. It describes briefly at five tragic events in which regulatory failures or, at least, shortcomings in the regulatory process were implicated. Some of the most dramatic reductions in accident rates usually involving individuals facing clearly defined hazards in particular situations have been brought about by the introduction of safety-related legislation combined with effective regulation and enforcement. Regulatory authorities are agents of social control. The organizational literature is rich in theoretical accounts of this control process, but the one favored here is that presented by Diane Vaughan in her detailed analysis of the Challenger accident. The recommendations of the Lord Robens Report later became enacted with remarkably little governmental tinkering as the Health and Safety at Work Act (HSW Act) in 1974. It was this Act that initiated the move towards self-regulation.