Membership with Sister Cities International is open to cities, counties, and states of all sizes. Members are a part of a network of citizen diplomats from over 500 communities with over 2,000 partnerships in 145 countries around the globe.

Sister Cities International provides essential services, programs, and resources to help members find partners as well as expand and improve their activities. Your membership provides you not only with access to unique tools and resources but also to dedicated staff assistance and guidance to build and grow a sister city program. Our staff have worked with hundreds of cities in countries around the world. Whether you are a volunteer, community leader, or municipal official, Sister Cities International can help you save time and money.

In addition to resources and expertise, membership with Sister Cities International ensures that your program is in the largest network of citizen diplomats in the world, and is a part of a peacebuilding tradition that has made the sister cities movement spread across the globe. With affordable rates based on the population of a community, Sister Cities International provides members with unique support and resources.

  • U.S. cities, counties, and states: CLICK HERE for more information on member benefits and how to join.
  • Non-U.S. cities, counties, and states (Global Membership): CLICK HERE for more information on member benefits and how to join.

To find out if your city is already a member please visit our City Directory. For more information please contact us at or call (202) 347-8630 and our membership department can answer any questions you might have.

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This year marks a pivotal moment during which Sister Cities International is celebrating 60 years of peace through people. Get involved in this momentous year.
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As the world becomes smaller, and connections online become more frequent than face-to-face interactions, multicultural understanding at the community level is more important than ever. Sister Cities International enables citizen diplomats in communities across the world to develop relationships with communities in other countries that are based on cultural understanding and mutual cooperation.Donate