Is language somehow innate in the structure of the human brain, or is it completely learned? This debate is still at the heart of linguistics, especially as it intersects with psychology and cognitive science. In collecting papers which discuss the evidence and arguments regarding thisdifficult question, The Inheritance and Innateness of Grammars considers cases ranging from infants who are just beginning to learn the properties of a native language to language-impaired adults who will never learn one. These studies show that, while precursors of language exist in othercreatures, the abilities necessary for constructing full-fledged grammars are part of the biological endowment of human beings. The essays that comprise this volume test the range and specificity of that endowment, while also contributing to our understanding of the intricate and complexrelationship between language and biology.