To study the effect of fees for interlibrary resource sharing, data were collected on all requests made to the State Historical Society of Wisconsin (SHSW) during a period when no charges were in effect (representing a normal baseline); during a period when the charges were announced, but not assessed; and during a period in which charges were in effect. In addition, an internal task analysis was made of the costs of providing interlibrary loan (ILL) services by SHSW, and other libraries known to be charging for ILL were surveyed. Results indicate that there is scanty evidence that fees affect ILL traffic, and that the income from the most common fee more than paid the incremental costs of setting up the fee system, although the extra recordkeeping is burdensome. It is concluded that, although further research on the effects of fees is warranted, it may be stated that fees can be a means of equitably distributing real costs of providing services to those who otherwise would pay nothing, and that such fees will not reduce traffic as much as direct user fees such as those charged to consumers of online services. Tables and figures are included, as well as a 33-item bibliography and an appended survey questionnaire. (KM)