This accessible book defines 100 key concepts, ideas and processes in Environmental Psychology to provide an introductory reference work that brings together research and theory in a bite-size format. With contributions from leading figures within Environmental Psychology, each concept is clearly defined and explained within the context of issues around the environment, sustainability, climate change, nature and architecture. This book considers the involvement of psychological, physiological and social processes to understand the mechanisms that explain and contribute to the evolution of behavior and attitudes that relate to our relationship with the environment. Concepts covered include biodiversity, eco-anxiety, place identity, sustainable behaviour, climate justice and environmental attitudes. By integrating ideas from different disciplinary orientations in the field of Environmental Psychology, this book allows for a better understanding of the processes related to the individual-environment relationship, as well as the applications that they allow for in various fields of intervention. This is essential reading for students and researchers in Environmental Psychology, Sustainability Studies, Architecture and Built Environment Studies and related fields.