This chapter defines bibliotherapy as psychotherapeutic programs presented in a written self-help format as opposed to fictional stories or religious texts. It outlines the research literature regarding the clinical effectiveness and cost-effectiveness of bibliotherapy for a wide variety of problems. It discusses the literature on process variables leading to therapeutic change in patients utilizing bibliotherapy. It addresses the role of bibliotherapy within the context of a stepped care and integrated care environment. It proposes adjunctive treatment as a research and dissemination agenda for the use of bibliotherapy. There are many obvious advantages to bibliotherapy over traditional psychotherapy such as the ability to self-pace, allowing individuals who are unable to receive mental health services due to geographical or transportational barriers receive treatment and providing cost-effectiveness for those who cannot afford psychotherapy or pharmacotherapy, privacy that can lessen stigmatization or labeling, and coping skills for life after treatment has ended. Despite these benefits, there are still many unknowns in the area of bibliotherapy such as for whom it is effective, for which psychological problems it is effective, what degree of adjunctive professional or nonprofessional help is needed, and what role bibliotherapy can play in integrated health care systems.