Urban sustainability is the idea that a city can be organized and designed to reduce negative environmental and social impacts on future generations. This can include considerations for air quality, clean water, proper waste treatment, buildings that are built to last, and even social equity. Sustainable cities work hard to ensure their citizens, infrastructure, and environments have the chance to thrive for years to come.

Urban sustainability has become increasingly popular in the United States in the past couple of decades. Sustainability though, is not a new concept at all. Nineteenth century planners Ebenezer Howard, Le Corbusier, and Frank Lloyd Wright pioneered planning sustainable cities. Then in the 20^th century, innovator Aldo Leopold wrote a piece entitled The Land Ethic, in which he began to encourage citizens to think more about the impact they were placing on the environment. Bill McKibben was thinking along the same lines as Leopold when he wrote, The End of Nature, which is considered the first book to discuss global warming written in an effort to gain public understanding.

In 1992, the United Nations hosted a summit in Rio de Janeiro, Brazil regarding environment and development, specifically sustainable development. The summit was considered a success because through it, many world leaders adopted the ideas of change in their home countries and have since implemented sustainable development practices in their cities. The success of the summit helped to create the widespread general consensus that the importance of sustainability cannot be denied, or else the future of our planet is in danger.

Since then, planners and scholars in the United States have been working hard to define the necessary components of sustainability and figure out how exactly they must be implemented in our modern democratic system. These ideas have been criticized though, with Agenda 21 being the particular target. As stated on sustainabledevelopment.un.org, “Agenda 21 is a comprehensive plan of action to be taken globally, nationally and locally by organizations of the United Nations System, Governments, and Major Groups in every area in which human impacts on the environment.”

Some people thought that these sustainable development practices gave the government too much power. Regardless, people like World Future Council Co-Founder Herbert Girardet, architect and urban designer/planner Peter Calthorpe, Princeton professor of climate change and systems ecology Stephen Pacala, and theoretical physicist and professor of mechanical and aerospace engineering Robert Socolow have been theorizing ways to gauge how much an area like a city is harming the environment, and how to combat that through urban planning.

Urban sustainability continues to be one of the most important issues of modern planning. Planners and builders have been working to create many different kinds of standards, like Leadership in Energy and Environmental Design (LEED) and Institute for Sustainable Infrastructure Envision Sustainability Professional (ENV SP) certifications, that offer certified professionals who can help people, companies, and government organizations plan and design for sustainability. Although many cities all over the United States are working toward being more sustainable, the future of comprehensive urban sustainability will require a complete ideological shift of most Americans.