Non-profit organization which manages the Sister Cities program. Originally a part of the National League of Cities, but became a separate organization in 1967 due to the popularity of the program.

Sister Cities Internationals official goals are:

• Develop municipal partnerships between U.S. cities, counties, states and similar jurisdictions in other nations.
• Provide opportunities for city officials and citizens to experience and explore other cultures through long-term community partnerships.
• Create an atmosphere in which economic and community development can be implemented and strengthened
• Stimulate environments through which communities will creatively learn, work and solve problems together through reciprocal cultural, educational, municipal, business, professional and technical exchanges and projects
• Collaborate with organizations in the United States and other countries which share similar goals