This library/archives is a research center for Pennsylvania Mennonite and Amish history, genealogy, and theology. It also holds a significant collection of historical/genealogical materials pertaining to southeastern Pennsylvania with a special focus on Lancaster County. The Society is a nonprofit, educational organization and is dedicated to the collection, preservation, and interpretation of books, papers, and artifacts related to the Anabaptist-Mennonite heritage.

Nonmembers of the Society pay a $5.00 per day fee to use the temperature-controlled library, but students may use the facilities free of charge. Most genealogies and local histories are shelved in the reading room, where researchers have access to open shelves. Additional books, maps, and archival items are housed in adjacent, limited-access areas, which require staff assistance for retrieval. Books are cataloged according to the Library of Congress classification system. Public computers with high-speed Internet access are available in the reading room. Microform readers, a reader-printer, and photocopier/printer are available for use.