This series documents the business practices of William Pahlmann Associates. While many of the other series in the William Pahlmann Papers detail aspects of the firm's operations such as the process of planning and completing jobs, networking with clients and other designers, and the firm's publicity efforts, the Office Files provide a look at how William Pahlmann Associates functioned as a business. These materials show how the firm kept its books, dealt with client billing, what types of insurance the firm carried, how they leased office and storage space, and how Pahlmann negotiated commissions and royalties on some of the products he designed. The Office Files Series offer researchers a view of William Pahlmann Associates' day-to-day operations from the perspective of the business office rather than the designer's drafting table.

Materials in the Office Files Series include examples of the firm's standard paperwork like time sheets, customer invoices, and accounting ledgers. This series also contains samples of client contracts, sample bids and proposals for large commercial jobs, correspondence with various parties, tables for estimating materials and costs, leases for office space, and insurance policies the firm carried.