In recent years the question of whether to use a period after the "S" in Harry S. Truman's name has become a subject of controversy, especially among editors. The evidence provided by Mr. Truman's own practice argues strongly for the use of the period. While, as many people do, Mr. Truman often ran the letters in his signature together in a single stroke, the archives of the Harry S. Truman Library have numerous examples of the signature written at various times throughout Mr. Truman's lifetime where his use of a period after the "S" is very obvious.
Mr. Truman apparently initiated the "period" controversy in 1962 when, perhaps in jest, he told newspapermen that the period should be omitted. In explanation he said that the "S" did not stand for any name but was a compromise between the names of his grandfathers, Anderson Shipp Truman and Solomon Young. He was later heard to say that the use of the period dated after 1962 as well as before.
Several widely recognized style manuals provide guidance in favor of using the period. According to The Chicago Manual of Style all initials given with a name should "for convenience and consistency" be followed by a period even if they are not abbreviations of names. The U.S. Government Printing Office Style Manual states that the period should be used after the "S" in Harry S. Truman's name.
Most published works using the name Harry S. Truman employ the period. Authors choosing to omit the period in their texts must still use it when citing the names of organizations that employ the period in their legal titles (e.g. Harry S. Truman Library) thus seeming to contradict themselves. Authoritative publications produced by the Government Printing Office consistently use the period in Mr. Truman's name, notably the Department of State's documentary series Foreign Relations of the United States, Diplomatic Papers, the Department of the Army's United States Army in World War II and two major publications of the Office of the Federal Register, Public Papers of the President - Harry S. Truman and the United States Government Organization Manual.