Given its age, size, and depth in languages and formats, the collection is strong in many special subject areas of religion and theology, subject areas that reflect the scholarly interests of donors and faculty and the evolving curriculum of the school. Areas of special strength are:
- Biblical Studies
- Protestant Christianity
- Unitarian Universalism
- Women's Studies in Religion
- Other Notable Subject Areas
In addition, there are many more specialized subject areas of exceptional strength. Examples include Christian ethics, Dead Sea Scrolls, Judaism and Christianity, religious freedom, Gnosticism, early Christianity, religion and politics, and the ecumenical movement. For detailed information on the library's collections by subject areas, see our Collection Development Policy.
The collection is further strengthened by its location among the great faculty libraries at Harvard and by its relationship with the member libraries of the Boston Theological Institute. This collection among collections serves as a gateway to the extraordinary resources of the many Harvard Libraries and is best used in conjunction with them.
For example, traditionally, Andover-Harvard Theological Library holds the Protestant collection of the University and Widener Library holds the Catholic. While Andover-Harvard collects reference and secondary literature in English on Islam, Buddhism, and Hinduism—increasingly so, given the trends in the curriculum—Widener and the Harvard-Yenching Library hold the major research collections, including titles in non-Roman scripts. While Andover-Harvard collects Judaica and Hebraica titles to support a strong biblical studies program, Widener holds the major collection on Judaism. While Andover-Harvard holds a significant number of rare books in religion and theology, the collection is small in comparison with the rich holdings of Harvard's Houghton Library. Still, it would be a mistake to overlook the AHTL collection in any of these areas. The Protestant Catholic division between Andover-Harvard and Widener is an oversimplification, since Andover-Harvard also collects important reference and secondary literature in Catholicism to serve a substantial number of Catholic students and faculty, while Widener Library holds the more in-depth collection in post-Reformation Catholic Church history, Catholic dogmatics, moral theology, and Catholic social action. Among the libraries of the Boston Theological Institute, Andover-Harvard holds the major collection on Unitarian Universalists, while other BTI libraries hold the major collections on Methodists, Evangelicals, Greek Orthodox, Episcopalians, and so on. Thus a collection strong in its own right is made stronger by access provided to other collections at Harvard, in the Boston area, and beyond. A former Divinity School librarian noted that "if we do not have it here, and we probably do, we can almost always get it for you."