In this book Norbert Hornstein, one of the most influential linguists working on syntax, discusses a topical set of issues in syntactic theory, including a number of original proposals at the cutting edge of research in this area. He provides a theory of the basic grammatical operations and suggests that there is only one that is distinctive to language. If this theory is correct then this narrows the evolutionary gap between verbal and non-verbal primates, thus facilitating the rapid evolutionary emergence of our linguistic capacity.