Urban street art has a rich history in both the culture and economics of the cities it is created.

The concept of street art includes not only unsanctioned designs like graffiti but commissioned works like sculpture, lighting displays, and wall murals.

Public art is the pushing of boundaries by presenting art in public contexts, outside of museums and galleries.

Street art emerged from its 1960s New York City graffiti-boom infancy to eventually gain some legitimacy as painters such as Keith Haring gained fame.

Still, it was years before what is now known as street art became a real career aspiration.

Today, numerous artists who began as street artists in New York, Philadelphia, Los Angeles, and other cities have transitioned to mainstream art, including commercial art.

Whether for the good of commercial or cultural interests, public art is recognized for its benefits to the urban environment in terms of its contribution to innovation.

Big City Street Art in the 20^th Century

While street art has a well documented beginning in New York City, which continues to serve as a mecca for creative talent, a well-known art funding program in Philadelphia has provided local artists employment and the city is now known as the 'city of murals'.

Other noteworthy street art cities in the Americas include all three of California's important cultural hubs – San Francisco, Los Angeles, and San Diego; Atlanta and Miami; Toronto, Canada; and the South American painting powerhouse cities of Sao Paulo and Buenos Aires.

In Europe, street art has a strong hold in London with a huge following, and in Berlin, widely considered the art capital of Germany, public art gained a notable medium in the form of the Berlin Wall, which stood from 1961 to 1989 and was a magnet to a wide array of painters.

Public art has flourished in other culturally diverse cities as Amsterdam where the group Amsterdam Street Art aims to elevate the status of public art there to the level of London, Paris, and Barcelona.

The Expansion of the Domain of Public Art

In recent years, public art has expanded its reach both in terms of its broader applications and also its range within the public realm.

This expansion of public art can be attributed to an increasingly engaged civic population, where the constituency participates in artistic direction and decisions.

The expansion of public art is sometimes attributable to the testing of ideas deemed too time consuming to subject to the political approval process.  Such art can be called accidental as it becomes acclaimed only after being installed on a trial basis for non-artistic reasons.

A particularly big-scale case-in-point is the installation of lighting across the San Francisco-Oakland Bay Bridge western span in 1986 to celebrate the 50-year anniversary of the opening of the bridge.

The lighting was an immediate and spectacular success with the public and became a nightly, enduring,  and endearing work-of-art.

Public Art as Political Expression

Public art has often been used to convey political dissension and has been effective in bringing about change.

Murals in Northern Ireland and Los Angeles were often created in times of conflict and helped bridge the societal gaps that effected their creation.

In the political murals of Northern Ireland, numbering some 2000 since the 1970's, many events during "the troubles" were fleshed out in murals and led to discussions and a measure of peace.

Several Los Angeles murals portrayed racial diversity in a city challenged by gang warfare and constant class struggle in relation to urban policies that favor the wealthy districts at the expense of the sprawling working class areas. The presence of murals has given the city a bridge to close a long-standing social gap.

Public Art and Urban Innovation Today

A surprising result of experimental or temporary public art has been the amazing public benefit from installations that have proved to be urban innovations.

In 2005, a San Francisco art and design studio turned a single car parking space outside its Mission District studio into a two-hour installation of a wooden deck with plants and seating.

The installation was so successful that a new concept was born and now there are numerous parklets in several cities.  This example of art turned urban innovation is perhaps a forerunner of an exciting future in sustainable urban planning by way of incrementalism.

By patronizing our artists and creative organizations through our donations of money and time, we ourselves foster the urban innovations that will lead our cities toward sustainability in the 21^st century.