A research guide prepared by Heidi Frostestad Kuehl, Foreign, Comparative, and International Law Librarian and Coordinator of Educational Programming and Outreach at Pritzker Legal Research Center, Northwestern University School of Law, Chicago. The guide has a general introduction to the subject with a list of key abbreviations, and covers treaties, national legislation, library catalogues, subscription databases, periodicals, environmental organisations, and other types of web site relating to international environmental law. The guide has been updated to May/June 2017, with four previous versions, published 2006-2013, also available.