High quality reprint of this recently declassified 1971 study. This report describes the effects of the Consolidated Republic of Vietnam Armed Forces Improvement and Modernization Program (CRIMP) on each of the Vietnamese Air Divisions (ADs). Each chapter of this report was written by a different author. Thus, the reader has not one, but five views of American efforts to improve and modernize the Vietnamese Air Force (VNAF). Each author presents the results of his own investigation, and while they generally agree on the overall success of the program, they sometimes differ on details. Problems and achievements that were significant to one author were sometimes less important to another. Therefore, each chapter of this report should be evaluated on its own merit as well as by comparison to the other four. The history of the VNAF and the United States Air Force (USAF) advisory role in its development has been traced in three previous CHECO reports: Organization, Mission and Growth of the Vietnamese Air Force, 1949-1968; VNAF Improvement and Modernization Program [1968-1970]; and The Vietnamization of the Air War, 1970-1971. The Vietnamization of the Air War is a companion volume to The VNAF Air Divisions: Reports on Improvement and Modernization. The former describes VNAF improvement and modernization (I&M) by mission function-- airlift" for example, or "logistics,"--and thus deals with the broad out lines of the entire VNAF. The VNAF Air Divisions, on the other hand, focuses on one Air Division in each chapter and investigates the details of I&M at the unit level. Together, these two volumes describe the VNAF as it developed between January 1970 and July 1971.