They spent over a decade turning their Maryland yard into bird and pollinator habitat, with native flowering plants and trees. Our research on HOAs has found that these private, quasi-governmental organizations are an often overlooked but influential force in environmental policy. While HOAs often act as barriers to residential environmental sustainability, we believe they could be bridges instead. HOAs have considerable environmental policy power, affecting how entire neighborhoods use water, generate energy, provide wildlife habitat and respond to climate change. We looked at 18 provisions affecting building structure, landscaping and energy and found that HOAs mostly presented barriers to residential sustainability.