The Ohio Model United Nations (OMUN) is a three-day simulation program in which student delegates represent selected member nations of the United Nations and participate in writing, presenting, and debating original resolutions that deal with current world problems, issues, and political situations. Student delegates also participate in global education contests, international talent showcases, and serve as student leaders of the program. OMUN was established as a classroom event for 100 students in southeastern Ohio in 1982. Since that time the program has grown and expanded to become the largest of its kind in Ohio and one of the largest in the nation. The program is sponsored by the Ohio Leadership Institute, a non-profit (501c3) educational organization in Columbus, Ohio.
Students in grades 9-12 can participate in the OMUN program. Each year twelve to fifteen hundred students attend from over fifty school districts in Ohio. During the past several years, students have also attended the program from New York, Arkansas, Kentucky, and Toronto, Canada. The annual three-day conference is held in either December or January. Over the last many years, it has been held at the Hyatt Regency Hotel in downtown Columbus. In addition to the conference, students begin preparations months in advance. Most students begin to prepare at the start of the school year and attend meetings after school during the fall. School advisors attend training sessions and use training materials in order to prepare students for the event.