This paper examines the factors that contribute to a library's decision to become involved in adult literacy and the service roles assumed by a given library. Common library literacy service roles (i.e., collections, services in support of local literacy efforts, and direct instruction) are discussed and profiles of the types of libraries that are involved in literacy education are given. Factors that contribute to a library's level of literacy involvement are then compared and contrasted among public libraries, community college libraries, institutional libraries, school libraries, state library agencies, and university libraries. Similarly, the types of literacy activities in which these libraries are involved are identified. One type of literacy activity, the family literacy program, is explored in more detail. It is observed that the effectiveness of the family literacy program stems from its holistic approach to literacy, in which both children's and adult services librarians blend their levels of expertise. Several funding sources for literacy education are reviewed, and it is suggested that the library's role as a partner in adult literacy education will continue to grow. (8 references) (MAB)