Interventions that affect children's vocabulary development focus on the quality of language as well as quantity. Children need opportunities to talk, use vocabulary words, and respond to adults' questions. Adults need to create opportunities to talk, provide quality feedback on children's language, and use a lot of new vocabulary repeatedly in meaningful contexts. Not every conversation a child has with caregivers can include all or even most of these facets of quality. Because the vocabulary gap is so difficult to close, young children at risk need the strongest early experiences that we can provide, grounded in decades of high-quality empirical research on this topic. Solutions for the word gap need to emphasize the content of conversations and the types of word learning, in the hope that our nation can ameliorate the "word gap" that is producing the achievement gap.