The U.S. Environmental Protection Agency (EPA) posted a September 2011 guidance document entitled Guidance to Facilitate Decisions for Sustainable Nanotechnology, which was prepared by the National Risk Management Research Laboratory of the Office of Research and Development. EPA states that it developed the guidance to assist in assessing the sustainability of nanoproducts, and it is intended “to lay the groundwork for developing a decision-support framework through continual updates as research in this area progresses.” The foundation of EPA’s approach, according to the guidance, is to consider existing standards and methods for environmental, economic, and social assessments using a life cycle perspective and offer guidance by relaying first-hand knowledge of applying assessment tools to nanotechnologies, whenever possible. The guidance includes overviews of various assessment methodologies to help stakeholders make informed choices when selecting tools appropriate for their goals. According to EPA, the key steps to be included in the evolving framework include: characterizing a nanoproduct and identifying potential risks and impacts; identifying relevant stakeholders; defining the goal and scope of an assessment; assessing environmental, economic, and social impacts; evaluating sustainability criteria; developing and evaluating alternatives; and selecting and implementing a decision to support sustainability. EPA will review and update the guidance as additional information becomes available.