A Model United Nations conference is a simulation of the work of the United Nations. Students represent countries and other bodies. They research an issue, agree a position, write resolutions with other delegations, debate them, and vote on them.
The debate follows a fixed set of rules. Those rules are the same for every committee. See Rules of Procedure overview.
A conference that follows THIMUN procedure runs over several days in a row. Each day has a different job.
The first day opens the conference. Most of it is lobbying. Delegates find allies and merge their draft resolutions into stronger ones.
The middle day or days are debate. Committees debate and vote on the resolutions that came out of lobbying.
The last day usually brings the General Assembly committees together for a plenary session. The conference then closes.
In MEDIMUN, the conference runs for three days and day three is a half day. It is held on the first weekend that falls entirely within February. That means the first Friday to Sunday where all three days are in February.
If the Friday is still in January. That weekend does not count. The conference is the weekend after. The 21st Session ran from 6 to 8 February 2026, because the 1st of February that year was a Sunday.
Each day has its own page. See Conference day one, Conference day two and Conference day three.
A conference has four groups of people.
Delegates. Students who represent a country or another body in one committee. They debate.
Chairs. Students who run a committee. A committee has more than one chair and they divide the work.
Staff. Students who run the operational side of the conference. They are organised into departments.
The people responsible for the whole event. The secretariat leads the student side. Adults hold overall responsibility.
Chairs and delegates do not do the same job, and staff are not delegates. See Who is who at a conference.
In MEDIMUN, a session involves roughly 400 delegates aged 15 to 19, around 60 school directors and about 100 student staff. Senior Directors and Directors are teachers and form the executive board. Everyone from Secretary-General down to Member is a student.
Committees come in types. In a General Assembly each delegate represents one country. A Security Council is much smaller and debates clause by clause rather than resolution by resolution. A Special Committee usually follows a procedure close to the Security Council. Delegates in a Special Committee often represent bodies rather than countries.
A Security Council has 15 members. Five of them are permanent members with a veto. See Security Council procedure and The veto.
In MEDIMUN, a session has 7 or 8 committees. The current session has eight. - GA1, GA2, GA3 and GA4. General Assemblies. - SC. Security Council. - HSC. Historical Security Council. - CHSC. Contemporary Historical Security Council. - SCOC. Special Committee on the Charter of the United Nations.
In MEDIMUN, everything is in English. That includes debate, lobbying, written work and conversation between staff. The only exception is an emergency. See Emergencies and incidents.
Only schools apply. An individual student cannot register alone. A school applies as a delegation and is granted one or more countries. See Delegation applications.
Every part of MEDIMUN runs on MediBook. A person without a MediBook account does not get a certificate and cannot attend. See MediBook is required.
If you are unsure where you fit into all of this, start from your role. A delegate reads What a delegate does. A chair reads Chair role and responsibilities. A teacher bringing a school reads School director role.
Before the conference for the preparation timeline.
What you need to take part for the account, the device and the consent.
Registration and attendance for how you are signed in each morning.
Daily schedule and breaks for how a day is timed.
Your first conference if you have never been to one.