Teach and Trade is a versatile vocabulary-building activity that the author's students love. It is designed to introduce key vocabulary in a learner-centered, engaging way and makes an upcoming unit or text more accessible. Learners become experts in one or two words and become familiar with most target words they subsequently come across. This activity, which the author developed after glimpsing her students participate in Quiz, Quiz, Trade (The Teacher Toolkit, n.d.) in another class, is appropriate for adolescent and adult English as a second or foreign language learners at all levels, and it can easily be adapted for younger learners.