Conversation so far:
where is the secretary of state's office located
The State Department is headquartered in the Harry S Truman Building, a few blocks away from the White House.
which neighborhood is the state department headquartered in
The State Department is headquartered in the Foggy Bottom neighborhood of Washington, D.C.
what is the address for the US state department
Harry S Truman Building, 2201 C Street Northwest, Washington, D.C., U.S.

Question: who leads the department
Self-contained rewrite: who leads the United States Department of State