• Alpha 1 Association Organization which attempts to identify those affected by alpha-1-antitrypsin deficiency and to improve their quality of their lives through support, education, advocacy and research.

• American Association for the Study of Liver Diseases (AASLD) A nonprofit, member organization serving the educational and scientific needs of its physicians, researchers, and scientists, who are striving to prevent and cure diseases of the liver and biliary tract.

• American Board of Internal Medicine The site includes information on certification, examinations, policies, and publications of the ABIM subspecialties(eg. internal medicine, gastroenterology).

• American College of Gastroenterology Organization involved in study and treatment of disorders of the gastrointestinal tract. The College promotes medical education and attempts to meet the needs of clinical gastroenterology practitioners.

• American Gastroenterological Association (AGA) society of physicians and scientists that serves as an advocate for its members and their patients; supports members' practices and scientific needs; and promotes the research and application of new knowledge leading to digestive disease prevention, treatment, and cures.

• American Liver Foundation Provides information about liver in health and disease, research funding, and patient related information.

• American Pancreatic Association fostering clinical and basic research in pancreatic disease. Includes news, member information, meeting notes, and links.

• American Partnership For Eosinophilic Disorders APFED is a non-profit organization cated to the patients and their families oping with eosinophilic gastrointestinal. APFED strives to expand education, create awareness, and support.

• American Society for Gastrointestinal Endoscopy Represents gastroenterologists, surgeons, and other digestive health specialists who are committed to diagnosis and treatment of GI disease through the appropriate use of endoscopic techniques.

• American Society of Bariatric Physicians (ASBP) National medical society of licensed physicians offering specialized programs in the medical treatment of obesity (bariatrics), weight loss and dieting.

• American Society of Colon and Rectal Surgeons Society of board certified surgeons. Promotes the science and practice of treatment of patients. Search for a surgeon, research, newsletter, and membership information.

• American Society of Gastrointestinal Endoscopy including meeting sites, informational brochures, links, and a case of the month.

• British Society of Gastroenterology Organisation focused on the promotion of gastroenterology within the United Kingdom.

• Canadian Association of Gastroenterology Organization of gastroenterology practitioners and researchers based in Canada.

• Canadian Digestive Health Foundation Dedicated to public education and promoting research to improve quality of life of Canadians with digestive disorders and their families.

• Canadian Hemochromatosis Society Volunteer based organization which provides information to patients and physicians about hemochromatosis.

• CCFA: Crohn's & Colitis Foundation of America American organization focused on improving the quality of life of people with Crohn's disease and ulcerative colitis through research. Provides information for both physicians and patients.

• Chesapeake Society of Gastroenterology Nurses and Associates group who practices in hospitals, ambulatory endoscopy centers, and physician offices to provide optimal care to patients during gastrointestinal procedures.

• Digestive Disease Week Organization of practitioners focused on digestive diseases.

• Digestive Disorders Associates specializes in the diagnosis and treatment of diseases of the digestive system.