Evolution of Department of Defense Directive 5100.01, "Functions of the Department of Defense and Its Major Components"

Abstract

This paper examines the evolution of Department of Defense Directive (DoDD) 5100.01, Functions of the Department of Defense and Its Major Components. Although the Directive itself was not formally issued until 1954, the document can trace its origins to the early 20th century. The Joint Action of the Army and the Navy, created in 1927 and later revised in 1935, was a non-binding agreement that spelled out the general and secondary functions of each Service. This paper examines the history of DoDD 5100.01, reviews its modifications, and identifies the factors leading to each change. It identifies key leaders who spearheaded the reforms and discusses legislation that led to noteworthy revisions of the Directive. Finally, this paper will conclude with a discussion about changes in organizational relationships, roles, missions, and functions that have occurred in recent years, and with observations about the necessary conditions for future reform.