| Academy of Molecular Imaging |
| Accelerated Cure Project for Multiple Sclerosis |
| Accreditation Association for Ambulatory Health Care |
| Administration on Aging |
| Administration on Developmental Disabilities |
| Adult AIDS Clinical Trials Group |
| Agency for Healthcare Research and Quality |
| Agency for Toxic Substances and Disease Registry |
| AGS Foundation for Health in Aging |
| AIDS Education Global Information System |
| Alagille Syndrome Alliance |
| Alcoholics Anonymous |
| Alliance for Lupus Research |
| Alpha One Foundation |
| ALS Association |
| Alternative Medicine Foundation |
| Alzheimer's Association |
| Alzheimer's Disease Education and Referral (ADEAR) Center (National Institute on Aging) |
| Ambulatory Pediatric Association |
| AMD Alliance International |
| America's Blood Centers |
| American Academy of Allergy, Asthma, and Immunology |
| American Academy of Audiology |
| American Academy of Child and Adolescent Psychiatry |
| American Academy of Dermatology |
| American Academy of Facial Plastic and Reconstructive Surgery |
| American Academy of Family Physicians |
| American Academy of Home Care Physicians |
| American Academy of Maxillofacial Prosthetics |
| American Academy of Medical Acupuncture |
| American Academy of Neurological and Orthopaedic Surgeons |
| American Academy of Neurology |
| American Academy of Neurology Foundation |
| American Academy of Ophthalmology |
| American Academy of Optometry |
| American Academy of Orthopaedic Surgeons |
| American Academy of Otolaryngic Allergy |
| American Academy of Otolaryngology--Head and Neck Surgery |
| American Academy of Pain Medicine |
| American Academy of Pediatric Dentistry |
| American Academy of Pediatrics |
| American Academy of Periodontology |
| American Academy of Physical Medicine and Rehabilitation |
| American Academy of Podiatric Sports Medicine |
| American Academy of Sleep Medicine |
| American Association for Geriatric Psychiatry |
| American Association for Hand Surgery |
| American Association for Marriage and Family Therapy |
| American Association for Pediatric Ophthalmology and Strabismus |
| American Association for Respiratory Care |
| American Association for the Study of Liver Diseases |
| American Association of Blood Banks |
| American Association of Clinical Endocrinologists |
| American Association of Diabetes Educators |
| American Association of Hip and Knee Surgeons |
| American Association of Kidney Patients |
| American Association of Neurological Surgeons |
| American Association of Neuromuscular & Electrodiagnostic Medicine |
| American Association of Oral and Maxillofacial Surgeons |
| American Association of Orthodontists |
| American Association of Poison Control Centers |
| American Association of Suicidology |
| American Association on Intellectual and Developmental Disabilities |
| American Autoimmune Related Diseases Association |
| American Behcet's Disease Association |
| American Board for Certification in Orthotics and Prosthetics |
| American Board of Bariatric Medicine |
| American Board of Hospice and Palliative Medicine |
| American Board of Pediatrics |
| American Board of Surgery |
| American Brain Tumor Association |
| American Burn Association |
| American Cancer Society |
| American Chronic Pain Association |
| American College Health Association |
| American College of Allergy, Asthma & Immunology |
| American College of Cardiology |
| American College of Chest Physicians |
| American College of Emergency Physicians |
| American College of Foot and Ankle Surgeons |
| American College of Gastroenterology |
| American College of Medical Toxicology |
| American College of Obstetricians and Gynecologists |
| American College of Physicians Foundation |
| American College of Physicians-American Society of Internal Medicine (American College of Physicians) |
| American College of Prosthodontists |
| American College of Radiology |
| American College of Rheumatology |
| American College of Sports Medicine |
| American College of Surgeons |
| American Council for Drug Education |
| American Dental Association |
| American Diabetes Association |
| American Dietetic Association |
| American Epilepsy Society |
| American Federation for Aging Research |
| American Foundation for AIDS Research |
| American Foundation for the Blind |
| American Gastroenterological Association |
| American Geriatrics Society |
| American Head and Neck Society |
| American Headache Association, Committee on Headache Education (American Headache Society, Committee on Headache Education) |
| American Headache Society |
| American Health Assistance Foundation |
| American Health Care Association |
| American Health Information Management Association |
| American Hearing Research Foundation |
| American Heart Association |
| American Hospice Foundation |
| American Hospital Association |
| American Institute for Cancer Research |
| American Institute of Biological Sciences |
| American Institute of Ultrasound in Medicine |
| American Kidney Fund |
| American Liver Foundation |
| American Lung Association |
| American Lyme Disease Foundation |
| American Medical Association |
| American Medical Society for Sports Medicine |
| American Occupational Therapy Association |
| American Optometric Association |
| American Orthopaedic Foot and Ankle Society |
| American Orthopaedic Society for Sports Medicine |
| American Osteopathic Association |
| American Osteopathic College of Dermatology |
| American Pain Foundation |
| American Pain Society |
| American Pediatric Surgical Association |
| American Pharmacists Association |
| American Physical Therapy Association |
| American Podiatric Medical Association |
| American Porphyria Foundation |
| American Pregnancy Association |
| American Psychiatric Association |
| American Psychological Association |
| American Public Health Association |
| American Red Cross |
| American Rhinologic Society |
| American Sleep Apnea Association |
| American Social Health Association |
| American Society for Bariatric Surgery |
| American Society for Clinical Pathology |
| American Society for Colposcopy and Cervical Pathology |
| American Society for Dermatologic Surgery |
| American Society for Gastrointestinal Endoscopy |
| American Society for Laser Medicine and Surgery |
| American Society for Microbiology |
| American Society for Reproductive Medicine |
| American Society for Surgery of the Hand |
| American Society for Therapeutic Radiology and Oncology |
| American Society of Anesthesiologists |
| American Society of Bariatric Physicians |
| American Society of Clinical Oncology |
| American Society of Colon and Rectal Surgeons |
| American Society of Echocardiography |
| American Society of Gene Therapy |
| American Society of Hand Therapists |
| American Society of Health-System Pharmacists |
| American Society of Hematology |
| American Society of Human Genetics |
| American Society of Interventional and Therapeutic Neuroradiology |
| American Society of Neuroradiology |
| American Society of Nuclear Cardiology |
| American Society of Ophthalmic Plastic and Reconstructive Surgery |
| American Society of Pediatric Hematology/Oncology |
| American Society of Plastic Surgeons |
| American Society of Radiologic Technologists |
| American Society of Transplantation |
| American Speech-Language-Hearing Association |
| American Stroke Association |
| American Syringomyelia Alliance Project |
| American Thoracic Society |
| American Thyroid Association |
| American Tinnitus Association |
| American Urogynecologic Society |
| American Urological Association |
| Angelman Syndrome Foundation |
| Anxiety Disorders Association of America |
| AORN |
| Aplastic Anemia & MDS International Foundation |
| Apraxia-Kids (Childhood Apraxia of Speech Association of North America) |
| Army Medical Department (U.S. Army Medical Dept.) |
| Arthritis Foundation |
| Arthroscopy Association of North America |
| Association for Professionals in Infection Control and Epidemiology |
| Association of Academic Physiatrists |
| Association of American Indian Physicians |
| Association of American Medical Colleges |
| Association of Regulatory Boards of Optometry |
| Association of Schools of Public Health |
| Asthma and Allergy Foundation of America |
| Ataxia-Telangiectasia Children's Project |
| Autism Society of America |
| College of American Pathologists |
| MayoClinic.com |
| Medicare |