OIO
| Acronym | Definition |
|---|---|
| OIO | Opera in the Ozarks (Eureka Springs, AR) |
| OIO | Oracle Inter Office |
| OIO | Offensive Information Operations (US DoD) |
| OIO | Overseas Investment Office (New Zealand) |
| OIO | Onderzoeker in Opleiding |
| OIO | Offentlig Information Online (Danish: Public Information Online; Denmark) |
| OIO | Open Infrastructure for Outcomes (medical software) |
| OIO | Open Infrastructure Offering |
| OIO | Office of the Investment Ombudsman (Korea) |
| OIO | Office of Independent Oversight (US Department of Education) |
| OIO | Operational Integration Office |