Education for Sustainable Development (ESD) works as an enabler to advance global Sustainable Development Goals of UNESCO’s Agenda 2030 Action Plan. Being literate in sustainable development is often determined by our ability to understand the language that is used to discuss sustainability issues. Language education has started to incorporate sustainability into institutional planning and the curricula of languages, and research on sustainable practices and the incorporation of ESD into language teaching has increased, but a comprehensive review of the effects of ESD on language learning that would consider both Western and the Global South perspectives is lacking. The concept of education is changing from teacher-centred and test-driven into more learner-centred and incorporating aspects of experiental learning and peer interaction, which are all aspects of the most transformational ESD approaches. Effective learning processes of ESD can further increase the quality and relevance of education. Based on recent research, this chapter takes the perspective of the learner and constructs a clearer picture of how ESD affects language learning both in the Western world and in the context of the Global South and discusses what is needed from ESD in language lessons for it to enhance learning that supports transformative actions.