- Sharif University of Technology (SUT), Tehran, Iran. Department of Mathematical Sciences: Professor. Teaching courses in undergraduate and graduate level. Including: Mathematical Analysis, Real Analysis, Abstract Algebra, Discrete Mathematics, Applied Algebra, Applied Linear Algebra, Probability, Statistics, Combinatorics, Graph Theory, and about twenty other different courses. (1983-present)
- Shahid Beheshti University, Tehran, Iran Department of Mathematics: Assistant professor (1979-1980).
- Community College of Philadelphia,
Philadelphia, Pa. Part-time faculty member (1973-1975), Visiting lecturer(1975-1976),Assistant professor in mathematics (1975-1979). Taught sections in mathematics for non-math majors.
- University of Pennsylvania,Philadelphia, Pa. Department of Mathematics: Teaching assistant. Taught recitation sections in calculus (1969-1975); taught courses (lecture and recitation) in calculus (Summer 1972,1973, and 1974).
- Shiraz University, Shiraz, Iran. Department of Mathematics and Statistics: Instructor. Taught first and second year mathematics for students indifferent majors. (1965-1969).
- Ministry of the Economy,Tehran, Iran Office of Industrial Statistics: Editor of data for the journal of this office (June-November 1965).
- Viting professor, Thaught course in:UQ and QUT(Australia) 1991, IASBS (Zanjan, Iran) 1993 and 2006.