This collection is primarily focused on the business dealings of Harry Paddock. The bulk of the collection is his letters, which mostly deal with land speculations in Minnesota and North Dakota. One topic that can be found in several letters is land speculation near Walker, Minnesota. This area was being considered for the site of a sanitarium, and Mr. Paddock was involved in attempted land sales to the organizers of the proposed facility. Another area of focus in the letters is lumber sales. Paddock owned lands in Northern Minnesota from which he would sell timber. A number of letters in this collection are concerned with the sale or transportation of lumber. Also included in the collection are Mr. Paddock's personal letters. These are both to and from his mother; niece, Mrs. Eva Chaplain of Mankato; and his nephew, Eugene Paddock.

There is one file of miscellaneous items. This includes Paddock's receipts from business transactions, transcripts of court decisions, and various personal receipts. Two ledgers are also contained in the collection, but have not been attributed to a specific business. They are not labeled, but appear to be from a real estate firm and a furniture store.