The U.S. Environmental Protection Agency (EPA) defines sustainability as meeting the needs of the present without compromising the ability of future generations to meet their own needs. In other words, sustainability attempts to balance the needs of people today with the future needs of our children and the natural systems that sustain all life. In an era of population growth, increasing economic competition, and environmental challenges ranging from climate change to air pollution and decreasing water levels to rising energy costs, planning is essential to our future and the well-being of our communities. Planning in the face of these challenges must transcend traditional zoning or general land use considerations. It can also promote sustainability by incorporating the three Es economy, environment and equity - in plans for development.