Today marks the official opening of the United Nations Conference on Sustainable Development, and representatives from government, public interest, industry, and intergovernmental organizations have gathered in Rio de Janeiro, Brazil, to address the environmental challenges facing our planet. Rio+20, as the international conference is being called, is an opportunity to take stock of progress that has occurred over the past two decades and the challenge of sustainable development that we face. It also represents an opportunity to advocate for more citizen involvement in environmental policymaking.