2 types of suicide cluster have been identified: mass clusters & point clusters. Mass clusters are media related & evidence for them is equivocal; point clusters are local phenomena & they do appear to occur. An alternative explanation is offered for why suicides sometime cluster: people who are at-risk for suicide may cluster well before the occurrence of any overt stimulus. When the group experiences events such as the suicidal behaviour of 1 member, the suicide risk of all members increases.