This two volume Handbook provides a comprehensive examination of policy, practice, research and theory related to English Language Teaching in international contexts. More than 70 chapters highlight the research foundation for best practices, frameworks for policy decisions, and areas of consensus and controversy in second language acquisition and pedagogy. The Handbook provides a unique resource for policy makers, educational administrators, and researchers concerned with meeting the increasing demand for effective English language teaching. The spread of English as a global language is well documented. In countries around the world, English has replaced other languages as the second language taught most frequently and intensively in school. These trends are escalating and have not yet reached their peak. Increasing demand for English language teaching is also evident among adult learners. Large-scale ELT programs for adult learners have been established in the community and workplace as a result of the globalization of the workforce, concerns to increase economic competitiveness, and a move towards life-long learning. Increased focus on English language teaching has also occurred in countries where English is the dominant language. Many English-speaking countries have experienced dramatic increases in immigration during the past 30 years.