1. Department of Chemistry, university of Khartoum, Khartoum, Sudan,

Professor (2007 – now).

2. Department of Chemistry, University of Qatar, Doha, State of Qatar.

Professor (2001 – 2006).

3. United States Environmental Protection Agency, Office of Solid Waste, Technology

    Innovation Office.  (1999 – 2001)

4. University of Qatar, Doha, State of Qatar, Visiting Professor (February-June

1998).).

5. LifeScan (a Johnson & Johnson Company), Milpitas, CA. (March-December 1997).

6. Educational Consultant (1995-1996) (Self- employed).

7. American University, Washington D.C.

Adjunct Professor (1993-1994)

8. Kuwait University, Kuwait City, State of Kuwait.

Professor (1983-1990).

Associate Professor (1977-1983).

Assistant Professor (1972-1977).

9. University College of Cape Coast, Ghana.

Lecturer (1971-1972).

10. University of Khartoum, Khartoum, Sudan.

Lecturer (1968-1970).