Most often, the term “duopoly” is used the context of business to identify those markets that are dominated by two primary suppliers who exert great influence. Examples would be Fedex versus UPS in overnight shipping within the United States; Pepsi versus Coca-Cola for worldwide soft drink sales; Republican verus Democrat in American politics, or Kindle versus Nook in electronic readers.

I propose that there is a very similar duopoly pattern for urban areas both in the United States and in numerous countries around the world. Here is my list of duopoly urban areas in the USA and Canada, as well as a partial international list:

Anchorage and Fairbanks, Alaska

Calgary and Edmonton, Alberta

Phoenix and Tucson, Arizona

Louisville and Lexington, Kentucky

Kansas City and St. Louis, Missouri

Omaha and Lincoln, Nebraska

Las Vegas and Reno, Nevada

Oklahoma City and Tulsa, Oklahoma

Toronto and Ottawa, Ontario

Philadelphia and Pittsburgh, Pennsylvania

Montreal and Quebec City , Quebec

Saskatoon and Regina, Saskatchewan

Sioux Falls and Rapid City, South Dakota

Milwaukee and Madison, Wisconsin

International

Brussels and Antwerp, Belgium

Sao Paulo and Rio de Janeiro, Brazil

Douala and Yaounde, Cameroon

Guayaquil and Quito, Ecuador

Cairo and Alexandria, Egypt

Athens and Thessaloniki, Greece

Nairobi and Mombasa, Kenya

Benghazi and Tripoli, Libya

Oslo and Bergen, Norway

Lisbon and Oporto, Portugal

Bucharest and Constanta, Romania

Moscow and St. Petersburg, Russia

Madrid and Barcelona, Spain

Stockholm and Goteborg, Sweden

Ho Chi Minh City and Hanoi, Vietnam

The lists provided above do not mean there are no other significant cities in these states, provinces, or nations, but the two cities listed tend to dominate culturally, demographically, socially, politically, and economically. Does that mean they always remain a duopoly? No. Just like companies, cities can falter and/or grow exponentially. In some instances a third or fourth city will rise in prominence to expand the duopoly into a triopoly or quadopoly. Four examples in the United States are:

Columbus, Ohio which has joined Cleveland and Cincinnati as dominant cities in Ohio by surpassing both in population, as well as being the political and educational epicenter of the state.

Orlando has joined Southeast Florida and the Tampa Bay region as an influential market in Florida, especially in the areas of tourism and broadcasting and media influence.

Both Austin and San Antonio have moved up to contend in some areas of influence with Dallas-Fort Worth and Houston in Texas. Austin in particular, is a dominant player in politics, education, technology, and culture in the state.

Both San Diego and San Jose have risen to contest the long-term leadership of the Bay Area and the Los Angeles region in California. San Jose (a.k.a. Silicon Valley) easily competes with any urban area on the planet in terms of its influence on technology.

International examples of cities that are contesting an existing duopoly include:

Vancouver and Calgary competing with Toronto and Montreal as dominant Canadian cities.

Perth and Brisbane challenging the duopoly of Sydney and Melbourne in Australia.

Several large cities in China, including Hong Kong joining Shanghai and Beijing as important centers of commerce.

Incheon joining Seoul and Busan in South Korea.

Izmir joining Istanbul and Ankara as a major player in Turkey.

In a few instances, when a third city rises to contend with the duopoly, one of the original members of this twosome falls out of favor or dominance. A possible example of this could be Kolkata, India as both Mumbai and Delhi have surged past this colonial capital in economic and political importance in recent decades.

The rise of a new contender does not always have to be organic. In some instances it can be a single critical action, decision, or event can starts the wheels in motion. For example, a number of nations have established a new national capital. This step immediately places that city on the national and worldwide political stage. Given enough time, the city may also rise as an economic and cultural center. An historic example is St. Petersburg, Russia which was built by Peter the Great as his capital city. While it is no longer the capital, St. Petersburg and Moscow have been a very competitive duopoly for many decades. Today, several other large cities in Russia have begun to complete with this twosome to a certain degree. But, when most people think of important Russian cities, the first two that come to mind are nearly always Moscow and St. Petersburg.

The discovery of a large reserve of petroleum, natural gas, or precious minerals could be another factor that changes the dynamics – both Calgary and Edmonton have benefitted in such a way. On the flipside, war and natural disasters are examples of events that could lead to a city rapidly falling from its dominant position

In conclusion, duopolies can occur in many aspects of our lives, whether it be in business, economics, sports and entertainment, politics, or urban and regional planning. For economic development planners, the intrinsically competitive nature of a duopoly can provide an impetus for fostering new ideas and innovation. At the same time, the two member cities of an urban duopoly can offer valuable urban planning lessens to one another from each other’s successes and failures. Considering that the other member of the duopoly in all likelihood faces many of the same challenges and constraints, where else would be a better resource to find potential solutions?

Unlike business duopolies which would run afoul with regulatory statutes, urban ones can and should work in unison whenever possible and practical to improve the greater good of both cities. My guess is that those urban duopolies that transcend their differences and feed off of each other’s combined knowledge base, will tend to have greater innovation and general community prosperity in the long term than those who remain at odds with one another or attempt to go it alone.