A survey of 1977 data from 12 magistrates' courts representing London, provincial cities, and rural areas showed a high rate of guilty pleas and findings of guilt among contested cases, but the rates for findings of guilt were slightly higher in nonpolice prosecutions. Estimates suggested that one-quarter to one-fifth of adult cases and nontraffic offenses brought to court were nonpolice prosecutions. The study also examined the Department of Health and Social Security; the Post Office; National Television License Records Office; Customs and Excise; the Health and Safety Executive; the Department of Trade; and the Ministry of Agriculture, Fisheries, and Food. Considerable differences in prosecution policy existed among and sometimes within these agencies, but all appeared to see their primary task as securing compliance with legislation through persuasion and education and did not fully exploit their potential for prosecution. Minor agencies also tended to be reluctant prosecutors, deploring police inactivity in their field but lacking resources to take independent action. There were virtually only two sources of private prosecutions: persons who brought cases for common assault under the 1861 Offenses Against the Person Act, which contains restrictions on police prosecutions of such offenses, and retail stores. Local authorities had low prosecution rates, although their broad range of enforcement activities would suggest a more active prosecutorial role. Other agencies reviewed included the Passenger Transport Executives, Regional Traffic Commissioners, public utilities, and special police forces. Finally, the study explores factors influencing an agency's prosecution policies and issues to consider in any reforms. Tables, over 50 references, legislation governing nonpolice prosecution, and descriptions of prosecutorial arrangements in the Greater London Council and West Germany are supplied.