The United Nation's Decade of Education for Sustainable Development (DESD) aims to prepare students for pressing economic and environmental problems. In this article, I argue that an exclusive emphasis on an ambiguous goal, sustainable development, raises important questions for educational ethics. Specifically, I argue that DESD mission statements and curricula often fail to account for trade-offs that are inevitable in environmental decision-making. Further, I argue that DESD aims don't adequately focus on the development of agency, decision-making skills, and ethical empowerment. I conclude by suggesting that ESD curricula should critically and constructively recognize the inevitability of trade-offs.