The Strong Collection is composed of land records, legal documents, correspondence, receipts, genealogical information, photographs, and other documents pertaining to the Bradt, Strong, and Van Patten families, collected by H. Elizabeth Strong (Hannah Elizabeth Vedder Strong). Strong appears to have collected this material primarily out of genealogical interest.

The bulk of the Strong Collection is composed of land records, legal documents, correspondence, receipts, and other documents pertaining to land and trusteeship of the city of Schenectady. The collection includes a significant amount of material related to early settlement of Schenectady, as well as the land and trusteeship disputes in the city that commenced from 1705 through 1795, when Ryer Schermerhorn, grandson and namesake of one of the original trustees, died. Frequently-named parties in the collection include Arent Bradt, Harmanus Bradt, John Lansing, Ryer Schermerhorn, Homer Strong, Simon Van Patten, Gerrit Veeder, Isaac Vrooman, and Jan Wemp. Several Dutch- language documents are included in the collection. Many of the early documents in the collection are handwritten copies of originals.

The collection also includes genealogical information related to the Strong, Van Patten, Lansing, Toll, Groat, Vedder, Weaver, Waterbury, and Pearse families, and receipts, correspondence, and other documents related to the Bradt, Strong, and Van Patten families.