Assistant professor (frequently capitalized as
Assistant Professor) is a tenure-track introductory level professor
academic rank used in the
United States,
Canada, and some other countries. It is generally taken after earning a
PhD and completing one or more
post-doctoral positions. It is often below the position of
associate professor and usually equivalent to
lecturer in English-speaking countries or to "Profesor Asociado" to "Profesor Titular" in Spanish-speaking countries.