Abstract The role in safety and purpose of accident investigation is followed by its brief history. The need to ban emotive and irrelevant judgemental terminology rejects the term `accident’ in favour of `damaging occurrence’. Complex Pattern and “Is” thinking is advocated. A damaging occurrence is understood via the participant, their aspects which interact in three different energy systems and the time zones of the occurrence. There is no cause, only a causation with a large number of essential and contributory factors. Factors influencing the information, willingness, resources and skills present at the damaging occurrence can be identified via the Information Chain and the Management Chain. Phylogeny and ontogeny are useful terms for classifying essential behaviour. Predictions of future occurrences is dealt with briefly. Consensus is challenged for its role in providing `consignorance’. This seminar concentrates on accident investigation. This paper provides the broad perspective necessary for effective accident investigation. Copyright© This work is copyright and is the Intellectual Property of the Author. You may download, display, print and reproduce this material in unaltered form only for your personal, non-commercial use or use within your organisation. Apart from any use as permitted under the Copyright Act 1968, all other rights are reserved. Requests and inquiries concerning reproduction and rights should be addressed to The InterSafe Group, PO Box 7338, East Brisbane, Queensland, Australia, 4169.