The National Science Foundation's Environmental Sustainability program is seeking grant proposals that promote sustainable engineered systems compatible with natural environmental systems. The program supports research in four principal areas: industrial ecology, green engineering, ecological engineering, and earth systems engineering. Proposals should be driven by engineering principles, address the novelty or transformative nature of the work, and discuss the potential impact on society and industry. The program encourages the involvement of graduate and undergraduate students, as well as the incorporation of social, behavioral, and economic sciences. Proposals that do not align with the Environmental Engineering or Nanoscale Interactions programs should be discussed with the program director prior to submission. Typical single-investigator awards range from $250,000 to $650,000 over 3 years, supporting one graduate student and up to one month of PI time per year. Faculty Early Career Development (CAREER) program proposals are strongly encouraged, with 5-year award durations. The program also considers proposals for conferences, workshops, supplements, and rapid response research as appropriate, which should be discussed with the program director before submission.