Presents the results of research on air interdiction in World War II, the Korean War, and the war in Southeast Asia. It outlines the lessons that can be learned from experience with air interdiction of ground-force operations, and suggests a number of factors that should be considered in planning and conducting an interdiction campaign. Section II describes the many different kinds of interdiction payoffs that have been sought and emphasizes their dependence on the specifics of the military situation on the ground. Section III describes the wide range of possible interdiction targets and discusses problems of matching targets with suitable weapons. Section IV illustrates the uncertainties that appear to be inherent in planning and conducting interdiction operations and emphasizes the need for timely intelligence, especially as to enemy responses. Finally, Sec. V provides what is, in effect, an annotated checklist intended for the use of those who are concerned with contingencies in which interdiction operations might be assigned a significant role.