United States Assistant Secretary of State

Assistant Secretary of State (A/S) is a title used for many executive positions in the United States Department of State, ranking below the under secretaries. A set of six assistant secretaries reporting to the under secretary for political affairs manage diplomatic missions within their designated geographic regions, plus one assistant secretary dealing with international organizations. Assistant secretaries usually manage individual bureaus of the Department of State. When the manager of a bureau or another agency holds a title other than assistant secretary, such as "director," it can be said to be of "assistant secretary equivalent rank." Assistant secretaries typically have a set of deputies, referred to as deputy assistant secretaries (DAS).
History.
From 1853 until 1913, the assistant secretary of state was the second-ranking official within the U.S. Department of State. Prior to 1853, the chief clerk was the second-ranking officer, and after 1913, the counselor was the second-ranking position, though the assistant secretary continued to be a position until 1924. From 1867, the Assistant Secretary of State was assisted by a second assistant secretary of state, and from 1875, by a third assistant secretary of state. Specific duties of the incumbents varied over the years and included such responsibilities as supervising the Diplomatic and Consular Bureaus, general supervision of correspondence, consular appointments, administration of the Department, and supervision of economic matters and various geographic divisions. 
Overview.
Today, the title of the second-ranking position is the Deputy Secretary of State, with the next tier of State Department officials bearing the rank of Under Secretary of State.
The following is a list of current offices bearing the title of "Assistant Secretary of State":
The following roles also possess a rank equivalent to Assistant Secretary:
Second Assistant Secretary of State.
The "Consular and Diplomatic Appropriations Act" for the year ending June 30, 1867 authorized the president to appoint a second assistant secretary of state. Duties of incumbents varied less over the years than did those of the other assistant secretary positions. Responsibilities included: supervision of correspondence with diplomatic officers; preparation of drafts of treaties, conventions, diplomatic notes, and instructions; detailed treatment of current diplomatic and political questions; approval of correspondence for the signature of the secretary or acting secretary; and consultation on matters of diplomatic procedure, international law and policy, and traditional practices of the Department. The Foreign Service Act of 1924 abolished numerical titles for assistant secretaries of state. Only two people held the position from 1866 to 1924.
Third Assistant Secretary of State.
A federal appropriations act for the year ending Jun 30, 1875 (Jun 20, 1874; 18 Stat. 90), authorized the president to appoint a third assistant secretary of state. The secretary of state was authorized to prescribe the duties of the assistant secretaries and other Department of State employees, "and may make changes and transfers therein when, in his judgment, it becomes necessary." The third assistant secretary's duties varied over the years, including such diverse assignments as: supervision of several geographic divisions; oversight of the bureaus of accounts and appointments; international conferences and commissions; and ceremonials and protocol, including presentation to the president of chiefs of foreign diplomatic missions. The Foreign Service Act of 1924 (May 24, 1924; 43 Stat 146) abolished numerical titles for assistant secretaries of state.