Series I in Boxes 1 - 12 contains case files for the State Highway Department, Norfolk and Western Railway, Virginia Auto Mutual Insurance, Appalachian Electric Power, and other corporations Collins represented including the theatre owner (Byers Theatre v. Murphy). This series also has his Commissioner of Accounts reports and files for individual private clients. These records covering 1933-42 were in folders numbered 1 to 217, although some of that number are missing; the numerical order has been retained.

Series II in Boxes 12 - 16 covers the same time period and were numbered (1 - 372 with many gaps) in the law office. This numerical arrangement is also roughly chronological. Many of these files contain one or two pieces of correspondence about relatively simple matters, although the contents of some of them relate to cases in the other series. Because Collins' various groupings for his files have been preserved, researchers will benefit from a careful reading of the box list when trying to follow a particular case.

Series III in Boxes 16 - 21 contains files that were in no particular order, so they have been arranged alphabetically. The types of cases here are similar to those in Series I, but the predominant years are the mid-1920's and the later 1940's