These organizational records span the history of the league during some of the minor league's most trying and successful periods in 20th century: the Great Depression, World War II, and the post-war boom and decline. This collection documents primarily the operation and financial aspects of a low minor league, colorfully illustrating the reasons for the decline of the Three-I League and general minor league decline in the 1950s. Box 1, folder 1 is an information folder which contains the finding aid.

The Three-I League minutes are extensive and document the organizational history of the league from 1937 through the decision to cease operations in January 1962. Throughout this period, these detailed minutes provide excellent documentation of the operation and finances of the league and its teams. The minutes appear to be comprehensive, including numerous annual and special meetings of the league.

Annual reports include extensive financial and attendance information for the league during the period from 1938 until 1961. In many cases, the annual reports include information found in part or in its entirety in the minutes. Specific information found in these reports include the league's financial statements, trial balances, attendance reports, receipts for playoffs and special dates, mileage pools and other relevant information.

The 1954 season documents include bulletins, memorandums, minutes, publications, and other sundry items comprehensively documenting public and private matters of the league. These documents were generated primarily by league president Hal Totten and maintained in his original order. The memorandums are particularly rich, documenting the communication between Totten and the clubs, team management, team managers, scorers, and umpires. Club memos include meeting agendas, general updates, clarifications of National Association issues and issues of concern to the team management, and pressing items concerning the league.