A country. A community. A relationship to explore.
Give your city a reason to connect. Explore community ties, compare industry definitions, and find the evidence and people who can help you choose a Sister or Friendship City to research.
World discovery now covers 251 countries, territories, and reporting economies, including the United States. The totals above describe the certified ready-lead release. See the expanded world coverage
Where is My Community?Where is My Sister(City)?
Sister & Friendship City research
Sister City Opportunity Index™
Explore potential city relationships through the released country-to-U.S.-market research leads and the international-city model.
Your city may want to help local firms reach new markets, connect colleges, or strengthen a community bond. Start with that purpose. Use the tools below to build a shortlist, then invite people in both places to shape the next step.
What the engine can help you do today: gather community evidence, explore the released leads, translate industry classifications, and check recorded connections. You choose the city shortlist; a confirmed foreign-city industry match still needs local industry records and a willing partner.
FIND A COMMUNITY STARTING POINT
Where could the next conversation begin?
The complete set includes 56 Sister City research leads and 13 diaspora outreach leads. Search a U.S. market or catalog country, then open a result to see its source evidence. The geography catalog is broader than this certified score release.
The displayed score is the Global Consumer Opportunity Index, a country-to-U.S.-market component. This research edition uses that published score directly. U.S. market areas may include several cities. Use this evidence to choose where to investigate a city relationship.
All 251 catalog geographies can be selected. This score release has published leads for 10 countries. Missing evidence does not mean no commercial opportunity. See the full coverage picture.
Explore 274 published community views, including 73 exact country-of-birth matches. See where communities live in the United States and follow the supported place questions.
First see what each place brings: three leading recorded entries and the full source profiles. Then explore broad common ground, supported numerical differences, and a question worth asking.
COUNTRY ↔ U.S. METRO · 2017 HISTORICAL EDITION
Meet the places. Then explore the connection.
First see each place’s three leading entries, where reported, and open their full source lists. Then explore broad common ground and the available numerical comparisons. This edition covers 203 countries and reporting economies and all 383 U.S. metros in the supplied GDP history, using 2017. A place does not need a Sister City score or a matched sector to show its own profile.
Start with two places you want to understand.
Choose a country and a supported U.S. metro. The result starts with each place’s leading reported groups and full lists. It then shows broad common ground, supported GDP-share comparisons, and sources you can save.
How do NAICS and ISIC help compare industry definitions?
NAICS describes industries in U.S. business data. ISIC provides an international reference. This separate code bridge uses U.S. NAICS 2022 and ISIC Rev.4. It lets you explore detailed classification links while keeping the older GDP sources’ definitions distinct.
Try a source example:
1 mapping row for “541511” · 1,706 rows in the complete source.
Read across each row: U.S. NAICS 2022 ISIC Rev.4. Several rows can describe branches of the same industry.
U.S. NAICS 2022
ISIC Rev.4
Scope of this mapping
541511Custom Computer Programming Services
6201Computer programming activities
No additional row qualification recorded. Read both industry definitions before using this link.
Source row 1684 · Source status: OFFICIAL_SOURCE
Source editions, partial links, and review rows
These are the supplied U.S. NAICS 2022 ↔ ISIC Rev.4 mappings. International records may use another national classification or edition; check that record’s system first. Many-to-many links must retain their notes and partial-industry flags.
All 1,706 rows remain in the download. One mapping uses source ISIC code 0331 outside the 419-class master, so 1,705 rows are included in default exploration. One other row’s partial flags could not be verified against its exact raw record. Both are labeled in the data.
ISIC classes 9810 and 9820 have no observed NAICS match in the supplied master. A missing correspondence is shown as missing; no replacement code is invented.
Source named in the supplied NDS table: U.S. Census Bureau concordance · Reference published October 23, 2026 · Industry definitions, with no change to index scores.
A source example: NAICS 541511 — Custom Computer Programming Services maps to ISIC 6201 — Computer programming activities. Use this common language to request more detailed local industry records. The mapping itself does not identify a buyer, a partner, or city industry strength.
BUILD ON PEOPLE AND PLACE
Who could help the connection take root?
Check existing city ties.
Review Sister City, Friendship City, and emeritus records from the SCI directory. Ask local hosts about their activity and interest in your idea.
Choose a question. Learn what to look for, why it matters, and what to do next.
RESEARCH PRIORITY · V1.0.0
Start with the score. Add context as you learn.
Research priority = the published Global Consumer Opportunity score. This edition needs only the released score, country, U.S. market, and source release. All 69 published leads can be explored now.
Community Bridge evidence appears beside each lead. City Population, Country Conversion, and Upstream Match Strength are optional context. They do not block this edition, and we do not add them to G again. G already contains upstream conversion, community, and affinity signals.
Higher G scores appear first. Equal scores share a priority rank; source lead IDs keep their original meaning. This identifies country-to-U.S.-market research priorities. It does not assign every foreign city a compatibility score or measure an existing partnership’s performance.
The earlier five-component international-city model remains available as a separate method. A new global city ranking can follow its own revised definition without holding back this research release.
All 69 rows from the source’s country-to-metro research table are included. The lead rank preserves its published order. Filters and score sorting change your view.
Geography stays visible
Country records use ISO3 codes. U.S. market areas use the source’s CBSA codes and may include multiple cities. Community bridge evidence uses country of birth.
Relationships need validation
Use the scores to choose research priorities. Verify city institutions, existing agreements, local participation, and business relationships before planning outreach.
Source and release
National Data System · Global Candidate V1.0.3 · certified October 14, 2026 · 30 passing source checks, zero warnings, zero failures. Reviewed from the supplied database inspection on October 20, 2026.
Release dates identify the build. The export does not separately establish every underlying observation period. Scores are research signals; partnership activity and economic results require their own evidence.
The wider six-pillar Commercial Diplomacy Index and the proposed Sister City Partnership Performance Index have separate methods.
Imagine a chamber wants to explore a new international relationship. Begin with a reason for both places to participate. A consumer-opportunity lead and a country-origin community estimate can help you choose where to look. They give you research priorities rather than an agreement or a confirmed buyer.
Keep the evidence you explored above together. Use the industry code bridge to describe the work in comparable terms, and city facts to identify places to research. Ask what a business, college, or community group in each place would gain from taking part.
The Follow Your Heart community directory offers another way to explore U.S. community presence. Read its Census label: ancestry, birthplace, and detailed identity describe different things and stay separate from this score.
Try this: Save a lead, choose a business or learning goal, and identify one willing host in each place before planning travel.
YOUR QUESTION. YOUR WORKING NOTES.
My Diplomacy Notebook
Keep your goal, research, sources, and next step together. Open this notebook from any page and continue where you left off.
Copy, download, and print include your goal, all saved notes, and saved research with its source details. For a PDF, choose “Save as PDF” in the print window.
Saved on this browser and device. Notes stay separate from contact forms. Clearing this site’s browser data removes saved notes. How notes are saved.