Oliver Sexsmith "Mike" Crosby (April 27, 1920 to October 25, 2014) was an American diplomat who served as United States Ambassador to Guinea.

[2] Between 1952 and 1953 Crosby studied German at Harvard University and, from 1964 to 1965 took additional courses at the National War College.

[2] Crosby served at the U.S. Department of State in Washington, D.C. from 1958 to 1962 as an intelligence research specialist before returning abroad as a political officer in Nicosia.

[2] From 1965 to 1968, Crosby was deputy chief of mission in Bamako, then country director for southern African affairs at the State Department from 1968 to 1972, and from 1972 until his 1977 appointment as United States Ambassador to Guinea, was deputy chief of mission in Lagos.

[1] This article incorporates public domain material from websites or documents of the United States Government.