| Abbreviations | Meaning |
 | ACN | Association For Comprehensive NeuroTherapy |
 | ACN | Association Of Camp Nurses |
 | ACN | Australian Cancer Network |
 | ACNEM | Australasian College Of Nutritional & Environmental Medicine |
 | ACNM | American College Of Nuclear Medicine |
 | ACNM | American College Of Nurse-Midwives |
 | ACNN | Association Of Child Neurology Nurses |
 | ACNP | American College Of Neuropsychiatrists |
 | ACNP | American College Of Neuropsychopharmacology |
 | ACNP | American College Of Nuclear Physicians |
 | ACNP | American College Of Nurse Practitioners |
 | ACNU / UNAC | Association Canadienne Pour Les Nations Unies / United Nations Association In Canada |
 | ACO / ASSO | Arbeitsgemeinschaft Für Chirurgische Onkologie Der Österreichischen Gesellschaft Für Chirurgie / Austrian Society Of Surgical Oncology |
 | ACO / CAO | Association Canadienne Des Optométristes / Canadian Association Of Optometrists |
 | ACO / CAO | Association Canadienne Des Orthodontistes / Canadian Association Of Orthodontists |
 | ACO / COA | Association Canadienne D'Orthopédie / Canadian Orthopaedic Association |
 | ACOA / CASLPA | Association Canadienne Des Orthophonistes Et Audiologistes / Canadian Association Of Speech-Language Pathologists And Audiologists |
 | ACOCA | AIDS Council Of Central Australia |
 | ACOEM | American College Of Occupational And Environmental Medicine |
 | ACOEP | American College Of Osteopathic Emergency Physicians |
 | ACOFP | American College Of Osteopathic Family Physicians |
 | ACOG | American College Of Obstetricians And Gynecologists |
 | ACOHM | Australian College Of Herbal Medicine |
 | ACOM / CAMO | Association Canadienne Des Oncologues Médicaux / Canadian Association Of Medical Oncologists |
 | ACOMS | American College Of Oral And Maxillofacial Surgeons |
 | ACON | AIDS Council Of New South Wales |
 | ACOOG | American College Of Osteopathic Obstetricians And Gynecologists |
 | ACOP / CAPO | Association Canadienne D'Oncologie Psychosociale / Canadian Association Of Psychosocial Oncology |
 | ACOPHRA | Association Consultative Et Promotionnelle Des Pharmaciens Hospitaliers De La Région Rhône-Alpes |
 | ACOPSA | American College Of Psychoanalysts |
 | ACOR | Association Of Cancer Online Resources |
 | ACOSOG | American College Of Surgeons Oncology Group |
 | ACOSS | Agence Centrale Des Organismes De Sécurité Sociale |
 | ACOSS | Australian Council Of Social Service |
 | ACP | Alliance Of Cardiovascular Professionals |
 | ACP | American College Of Phlebology |
 | ACP | American College Of Physicians |
 | ACP | American College Of Prosthodontists |
 | ACP | American College Of Psychiatrists |
 | ACP | Analytical Cellular Pathology [periodical] |
 | ACP | Association For Child Psychoanalysis |
 | ACP / CAP | Académie Canadienne De Parodontologie / Canadian Academy Of Periodontology |
 | ACP / CAP | Association Canadienne Des Pathologistes / Canadian Association Of Pathologists |
 | ACP / CPA | Association Canadienne Des Paraplégiques / Canadian Paraplegic Association |
 | ACPA | American Chronic Pain Association |
 | ACPA | American Cleft Palate-Craniofacial Association |
 | ACPA | Australian Cerebral Palsy Association |
 | ACPE | American College Of Physician Executives |
 | ACPE | Accreditation Council For Pharmacy Education |
 | ACPGBI | Assocation Of Coloproctology Of Great Britain And Ireland |