To deliver changes towards sustainability SEA should influence the implementation, rather than the formulation, of strategic initiatives. In this light, SEA follow-up that relates to post-decision activities of SEA and strategies becomes crucial. This book inquires whether SEA follow-up is feasible and relevant and, if so, when and how it can be effective and useful. It proposes and tests a framework to examine, evaluate, and explain the current practice of SEA follow-up based on an e-survey and case studies from England and Canada. The book reveals important explanatory linkages between the follow-up elements, strengths and weaknesses, and problems and benefits; derives key messages for advancing the SEA follow-up theory and practice; and makes recommendations. The book contends that by tailoring the proposed SEA follow-up framework to a particular strategy-making/realisation process, organisational structure, and context SEA follow-up can be made useful and effective. Moreover, the framework, linkages, messages, and recommendations can help shape or improve SEA follow-up. This book can be used in educational and practical purposes by SEA researchers, students, and practitioners.