Four distinct stages apply to liability claims. 1. The cause (e.g. spillage of toxic chemical onto grazing land) the initial act. 2. The effect (cows ill after grazing ) – the occurrence. 3. Discovery of injuries – the manifestation. 4. Action the making of a claim. The sequence may be lengthy or virtually instantaneous e.g. workman burns down a house. Any one stage may be used to trigger a claim. Public liability policies are usually occurrence policies, i.e. the injury/damage must occur within the policy period regardless of the time of the initial act or of the claim. In long-tail disease claims and gradual pollution many years may separate the ‘occurrence’ from the ‘manifestation’. Professional indemnity insurance is ‘claims-made’, a stage 4 trigger. See OCCURRENCE TRIGGER THEORIES; TRIPLE TRIGGER THEORY. See Figure 5. – –