This is an ethnographic study concerned with recording phenomena observed, in most instances, in metropolitan Melbourne. The bulk of the field work consisted of lengthy, unstructured discussions with contacts in the working-class pubs of the inner suburbs over a period of 3 years. Three themes emerge from an analysis of the field work. First, the interaction between members of the public and the police in the process of criminal investigations is rarely one of unilateral action; it usually involves two-way communication. This is evident throughout all the field data presented in the book. Second, the interaction between members of the public and the police in obtaining information in criminal investigations is often best characterized as a process of "bargaining." In the specific instance of the police recruitment and management of informers ("gigs"), the bargaining is distinctively intricate. The data suggest a configuration in which the potential informer holds an asset needed by police (information); and the police interrogator holds an asset that can benefit the potential informer, i.e., the largely unfettered discretion to prosecute; however, the use of bluff and deception adds a further dimension to the "bargaining." The third theme is that the bargaining power held by police is often constituted in their ability to establish a configuration in which their source "chooses" to provide information within a restricted range of other options. This theme concerns who tends to be the "winner" in the sort of bargaining configurations identified in the data. Police largely define what constitutes information useful in crime investigations and the modes in which citizens may or may not supply such information; tactically, they manipulate the parameters of the discourse within which the citizen may act. Appended supplementary information, 273 references, a list of cases cited, and a subject index