OPSA
OPSA commonly denotes professional and governmental bodies in South Africa, including the Association for Office Professionals, a public‑safety accountability office, and academic advising services.
Miscellaneous
Community
Overseas Plastic Surgery Appeal
Omaha Pet Sitters Association
Owens Park Students Association
Oklahoma Private School Association
Governmental
Academic & Science
Office of Professional School Advising
Oklahoma Political Science Association
Oak Park String Academy