Sustainability is a new academic field and there is a lot of diversity in the programs. Check them out -- carefully.
New England College
Masters of Science in Management-Sustainability
This online program is designed to provide you with new ideas for better management and assist you in gaining the knowledge and skills you'll need to become a leader in businesses that are socially, environmentally, and economically responsible. Program Curriculum Includes: Examination of alternative and renewable energy sources; Principals and models of sustainable business management; Environmental law; Community advocacy and corporate social responsibility.
University of Vermont
Maters Certificate in Sustainable Campus Innovation
"Establish yourself as an environmental leader with a Master Certificate in Sustainable Campus Innovation. Gain the knowledge and skills to motivate the entire campus community in fostering a culture of environmental responsibility, and to implement sustainable operations policies that can lead to a healthier environment, a stronger institution and improved student life."