December 4-7, 2025
Fairmont Chicago Millenium Park

It's your world.
Fix it.

Welcome to CIMUN 2025 - Chicago's premier Model UN experience where high school delegates tackle global challenges through innovative diplomacy, realistic portrayal of national interest, and strategic problem-solving.



The 22nd annual Chicago International Model UN features our unique simulation style that mirrors real-world international relations, developed by the Institute for Diplomacy Education and Advocacy (IDEA).

December 4-7, 2025
Fairmont Chicago Millennium Park
200 N Columbus Dr, Chicago, Illinois

What Sets CIMUN Apart

CIMUN delivers an unparalleled educational experience that transforms how students understand global politics and diplomacy.

Real-World Diplomatic Challenges

Our conferences mirror actual international relations dynamics, preparing delegates for future leadership roles while building crucial skills in negotiation, public speaking, and strategic thinking.

Experience Diplomatic Interconnection

Unlike traditional Model UN conferences, CIMUN features fully integrated committees where actions in on as e body directly impact others. Delegates must collaborate as country teams to advance their national interests across multiple fronts simultaneously.

Our unique awards system recognizes both diplomatic expertise and political innovation, rewarding delegates who master their country's position while demonstrating adaptability in complex scenarios.

Dynamic Crisis Simulations That Evolve in Real-Time

Our dedicated crisis staff creates breaking developments throughout the conference, challenging delegates to respond to unexpected events just as real diplomats must do.

CIMUN 2025 Spotlight:

This year features our most ambitious integrated simulation yet, including our acclaimed Historical Simulation set in 1956. Delegates will navigate complex geopolitical challenges in a unique historical context.

Opening Ceremonies & Banquet

Begin your CIMUN experience with our elegant opening plated banquet featuring distinguished speakers from diplomatic and international affairs backgrounds. This formal plated dinner provides delegates the perfect opportunity to network with peers and faculty while setting the professional tone for the conference.

CIMUN 2025 Featured Committees

Historical Simulation: 1956

Step back to 1956 where delegates will navigate the complex diplomatic landscape of the Suez Canal Crisis. This simulation challenges participants to rewrite history through strategic diplomacy and coalition-building

It's your world. Fix it.

Welcome to the 21st annual Chicago International Model UN. CIMUN features the unique Model UN style developed by the Institute for Diplomacy Education and Advocacy (IDEA).

Join Our Elite Staff Team

CIMUN staff members represent the best of the Model UN community - diverse university students and young professionals passionate about creating exceptional educational experiences.

Historical Simulation: 1956

University students and graduates: Apply to join our committee, simulations (crisis), and administrative teams.

Technology-Enhanced Diplomacy

  • CIMUN News Network: Daily video broadcasts covering conference developments

  • Interactive Crisis Updates: Real-time information delivery to committees

"Alive and breathing comes to mind... The strength of this conference is the cross simulation crisis. Very real life."

Linda Bowman-Jones

Edens Senior High School (Edens, NY)

We go to 8 conferences, CIMUN is the best!

Diane Haleas

St. Ignatius College Prep (Chicago, IL)

"CIMUN's simulation is engaging, educational and challenging."

Adam Osmanski

Carl Sandburg High School (Orland Park, IL)

[IDEA] created a Model UN conference that keeps delegates and advisors coming back for more.

Best Delegate.Com

"...inspiring kids to care about their world."

Gwyneth Connel

Millbrook School, (Millbrook, NY)

The Patricia Leahy Fellowship for Educators

This prestigious fellowship honors exceptional Model UN faculty advisors with professional development support and a generous cash stipend. Named for Patricia Leahy, beloved Model UN Advisor at Hinsdale South High School, this program recognizes educators who demonstrate outstanding commitment to Model UN education.

Upcoming Events & News

03/01/2025

IDEA/CIMUN Staff Alumni Get together

Find out more about the Spring All Staff Alumni, friends and family gathering, coming soon to a rooftop in Chicago this spring.

01/04/2025

Best MUN conferences in Chicago

What are the best Model UN conferences in Chicago? Click here to find out more

05/04/2025

CIMUN Style Simulation

Learn more about our unique Model UN simulation style that emphasizes realistic portrayal of national interest and a fully-integrated simulation environment.

Ready to Experience CIMUN?

Join hundreds of passionate delegates from across the world for four days of diplomatic immersion, skill-building, and unforgettable connections.

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