Documentation for the collection is drawn from the published works of both George and Winifred Harley and from information accompanying the packing list for the objects. Another form of documentation is the correspondence surrounding acquisition of the collection. This provides a window into the motives of both the donor and the collecting institution, along with additional information about the objects themselves. A number of letters support the documentation of the Harley Collection.
The documentation and each object are connected through an accession number, which is used as the official designation for each object in the collection. Accession numbers are used rather than descriptive terms because they have the advantage of not being subject to change or reinterpretation.
The format of accession numbers assigned to this collection contain various pieces of information. For example:
- 65: The calendar year in which the Harley Collection was acquired.
- 01: The Harley Collection was the first collection acquired by the department in that year.
- 0037: The unique sequential number assigned to that object. In this collection, the numeration follows Harley's packing list of April 1965.