Recognizing the importance of vocabulary for comprehension, Wilhelm asks two key questions: "which words do I teach and how should I teach them?" Through years of trial and error, Wilhelm has adopted these principles to answer "which words": teach "important" words students will see and use again; words necessary to conceptual understanding; words that serve as gateways to other words and concepts. As for how to teach them, Wilhelm emphasizes teaching in context to increase retention of the word and to support engagement with the subject matter. He elaborates with specifics on instruction and student activities that have proven valuable. He ends with a reminder that teaching and learning vocabulary is essential to academic success for all students, including ELLs, and to the struggle for equality and civil rights.