This chapter introduces the section of Linking Ecology and Ethics for a Changing World on Ethics, Epistemology and Justice, three of the major concerns of environmental philosophy. It provides an overview of the chapters that constitute this section by Palmer, Longino, Hayward, Northcott, Eliot, and Mallory and picks out important themes that link these chapters. In particular, this chapter focuses on questions of scientific knowledge, the role values play in science (as discussed in Longino's paper) and what kinds of things in the environment might be thought of as being valuable (discussed in Palmer's and Eliot's papers). The chapter also provides an outline of different approaches to global environmental justice as developed by Hayward, Northcott and Mallory. Hayward focuses on the idea of 'ecological space', Northcott on climate injustice, and Mallory on the importance of recognizing issues of gender and race in any discussion of environmental justice.