One researcher has suggested an additional discouragement role, "managers" who monitor places. In this context, the routine activity approach can be viewed as two triplets, with potential offenders, targets, and places monitored by guardians, handlers, and managers, respectively. Another researcher notes varying degrees of responsibility for discouraging crime; his ideas are adapted to current purposes, listing four steps of crime discouragement: (1) personal discouragement, exerted by family and friends; (2) assigned discouragement, by those so employed; (3) diffuse discouragement, by those employed but not assigned to that specific task; and (4) general discouragement, by unpaid persons lacking a personal tie or an occupational responsibility. Linking these four steps with the two triplets concept above results in 12 types of crime prevention. 20 references, 3 notes, and 2 tables