This research focuses on the role social equity has played in sustainable development since the 1990s using the inclusion of affordable housing as a metric. Through the collection and examination of 492 sustainable‖ and ―smart growth,‖ mixed-use developments it was identified that less than 40 percent included affordable housing. While this suggests that some progress has been made in the efforts to address social equity in development, it also indicates a significant disparity in the intended beneficiaries of sustainable development.

In development practice, environmental justice has taken several forms. For instance, environmental justice laws may prevent an energy plant from being built if the pollution were going to disproportionately impact a group of people based on the aforementioned factors. In terms of housing policy, environmental justice laws have changed the U.S. Department of Housing and Urban Development‘s approach to building low income housing. Rather than segregating large public housing projects from the rest of the community, where residents would have more equal access to municipal services and benefits, HUD now encourages mixed-income and dispersed affordable housing development. For the purposes of this paper, it is especially important to note that no income group should bear a disproportionate cost of governmental policies based on environmental justice law.