The authors believe that a systematic organizational approach to aviation safety must replace the piecemeal approaches largely favoured in the past, but this change needs to be preceded by information to explain why a new approach is necessary. Accident records show a flattening of the safety curve since the early Seventies: instead of new kinds of accident, similar safety deficiencies have become recurrent features in accident reports. This suggests the need to review traditional accident prevention strategies, focused almost exclusively on the action or inactiona s of front-line operational...