* Associate Professor, Department of Biotechnology, Indian Institute of Technology Madras, Chennai-600 036(June 2004-Present)
* Head, Pharmacology Divison, Drug Discovery Group, Lupin research Park, Pune, Maharashtra(Jan 04 - June 04)
* General Manager and Group Leader, Department of Biochemistry, Cadila Healthcare Ltd, Ahmedabad, 380015(March 04 - June 04)
* Assistant Scientist (Res. Astt. professor), Division of hematology, Department of Medicine, Indiana University Medical center, Indianapolis, IN 46202 USA(July 99 - March 00)
* Associate Professor, Department of Biotechnology, National Institute of Pharmaceutical Education & Research S.A.S. Nagar (Near Chandigarh) 160062 India(Jan.98 - July 99)
* Visiting Associate Professor, Department of Biochemistry, Panjab University, Chandigarh-160014,India(Aug 97 - Dec. 97)
* Research Assistant Professor, Department of Medicine, Division of Hematology/Oncology, University of Pennsylvania Medical Center, Philadelphia, PA 19104, USA(May 97 - Aug 97)
* Senior Scientist, Department of Medicine, Division of Hematology/Oncology, University of Pennsylvania Medical Center, Philadelphia, PA 19104, USA(April 95 - April97)
* Visiting Research Associate, Microbiology Department Indiana University Medical Center, Indianapolis, IN 46202, USA(Aug. 94 - Feb. 95)
* Staff Fellow, Medicine Branch, Division of Cancer Treatment, National Cancer Institute, NIH, Bethesda, MD 20892, USA(Oct. 91 - May 93)
* Lecturer, Division of Hematology/Oncology, School of Medicine, Indiana University Medical Center, Indianapolis, IN 46202, USA(Feb. 91 - Oct. 91)
* Postdoctoral Research Fellow, Division of Hematology/Oncology, School of Medicine, Indiana University Medical Center, Indianapolis, IN 46202, USA(May 86 - Feb. 91)
* Scientist Pool Officer, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India(April 85 - April 86)
* Research Associate, Microbiology Department, Institute Gulbenkian De Ciencia, Oerias, Portugal(May 84 - Dec. 84)
* Demonstrator, Department of Biochemistry, M.L.B. Medical College, Jhansi, Uttar Pradesh, India(March 78 - Aug. 78)