In July 2025, Yokohama was featured in a global strategic toolkit for city, state, and regional governments on engaging internationally. The Toolkit, titled “Global Engagement, Local Benefits: A Strategic Toolkit for City, State, and Local Leaders,” was published by the Meridian International Center, a non-profit organization dedicated to strengthening international cooperation through diplomacy, culture, and leadership exchange, in collaboration with the Truman Center for National Policy and the Melbourne Centre for Cities.

This Toolkit aims to provide local leaders with practical, outcome-oriented guidance on how to conduct international engagement strategically, especially in a world where diplomacy is no longer the sole domain of national governments. It draws on cases from nine countries: Australia, Canada, France, Germany, Italy, Japan, New Zealand, the United Kingdom, and the United States, and highlights how sub-national entities engaging globally can lead to local benefits in economic development, sustainability, and resilience.

Yokohama is introduced in the Toolkit as one of the key examples from Japan, featured through two case studies:

• The Yokohama-Odesa Sister City Relationship
  Originally established in 1965, this partnership has remained active even amid the ongoing crisis in Ukraine. Yokohama’s continued support, including citizen-led fundraising, provision of water purifiers and the signing of an MoU in 2023 for post-conflict infrastructure cooperation, was highlighted as a resilient and impactful example of city diplomacy.

• Y-PORT and the Asia Smart City Conference (ASCC)
  Yokohama’s international technical cooperation with cities across Asia is spotlighted as a successful model for city-to-city collaboration. Projects with Mandaue City in the Philippines (waste management) and with Bangkok Metropolitan Administration (climate cooperation) are cited as examples of how urban partnerships can advance sustainable development while creating business opportunities.

Yokohama’s inclusion in the Toolkit was catalyzed by its participation in the Symposium on Strategic Subnational Diplomacy, held in Washington, D.C. in January 2025. The event brought together local leaders, researchers, and international affairs experts to explore how subnational diplomacy can address global challenges. The Toolkit was developed as a key outcome of this symposium.

Yokohama will continue to strengthen its role as a globally connected city, leveraging international partnerships to drive innovation, sustainability, and inclusive growth from the local level.