The first question that usually arises is whether a detective shall or shall not be employed at all in any particular case. Usually the most important thing is to find out what the real character, past, and associations of some particular individual may be. Well-established detective agencies with offices throughout the country are naturally in a better position to acquire such information quickly than the private individual or lawyer, since they are on the spot and have an organized staff containing the right sort of men for the work. If the information lies in your own city you can probably hire some one to get it or ferret it out yourself quite as well, and much more cheaply, than by employing their services. The leads are few and generally simple. The subject's past employers and business associates, his landlords and landladies, his friends and enemies, and his milkman must be run down and interrogated. Perhaps his personal movements must be watched. Any intelligent fellow who is out of a job will do this for you for about $5 a day and expenses. The agencies usually charge from $6 to $8 (and up), and prefer two men to one, as a matter of convenience and to make sure that the subject is fully covered. If the suspect is on the move and trains or steamships must be met, you have practically no choice but to employ a national agency. It alone has the proper plant and equipment for the work. In an emergency, organization counts more than anything else. Where time is of the essence, the individual has no opportunity to hire his own men or start an organization of his own. But if the matter is one where there is plenty of leisure to act, you can usually do your own detective work better and cheaper than any one else. Regarding the work of the detective as a spy (which probably constitutes seventy-five per cent of his employment to-day), few persons realize how widely such services are being utilized. The insignificant old Irishwoman who stumbles against you in the department store is possibly watching with her cloudy but eagle eye for shoplifters. The tired-looking man on the street-car may, in fact, be a professional "spotter." The stout youth with the pince nez who is examining the wedding presents is perhaps a central-office man. All this you know or may suspect. But you are not so likely to be aware that the floor-walker himself is the agent of a rival concern placed in the department store to keep track, not only of prices but of whether or not the wholesalers are living up to their agreements in regard to the furnishing of particular kinds of goods only to one house; or that the conductor on the car is a paid detective of the company, whose principal duty is not to collect fares, but to report the doings of the unions; or that the gentleman who is accidentally introduced to you at the wedding breakfast is employed by a board of directors to get a line on your host's business associates and social companions.