Vocabulary is central to English language teaching. Without sufficient vocabulary, students cannot understand others or express their own ideas. Teachers who find the task of teaching English vocabulary a little daunting are not alone! This easy-to-follow book presents important issues from recent vocabulary research and theory so that teachers may approach teaching vocabulary in a principled, thoughtful way. Topics covered are understanding vocabulary, importance of vocabulary, relevant research findings, students' vocabulary levels, and teaching vocabulary effectively. This revised volume contains two new chapters - Technology and Online Resources for Vocabulary Learning and Teaching and Using Word Lists in Vocabulary Teaching. New references and updated research, as well as new web links, activities, charts, and a detailed lesson plan for teachers to consider, are also included. The book is practical for English language teachers in any context and provides helpful reflections.