professional societies and committees
| 1994 - 2003 | Chairperson, American College of Gastroenterology Abstract Selection Subcommittee, Small Intestine and/or Pancreatic Disorders |
| 1996-Present | Founder and honorary president of Turkish Gastroenterology Research Foundation. |
| 1999 - 2001 | Chairperson, Educational Affairs Committee of American College of Gastroenterology. |
| 1999 - 2003 | Member, International Liaison Committee, American Gastroenterology Association. |
| 2000 - 2002 | Member, Board of Directors of American College of Gastroenterology Institute for Clinical Research and Education |
| 2001 - Present | Member, Advisory Medical Board of Prometheus Laboratories |
| 2001 - Present | Member, Advisory Medical Board of Centocor, Inc. |