This volume bridges the knowledge gap between second language acquisition researchers and second language pedagogy professionals in its focus on a topic of mutual interest: input. The reader-friendly contributions from seasoned researchers including Stephen Krashen, Bill Van Patten and new voices offer a wide range of existing and new perspectives on the matter of input. A rare feature of the book is that it includes extensive coverage by experts including James Flege and Alene Moyer of the acquisition of the sound system of a second language, where input seems to matter most. Those who are just making their acquaintance with second language acquisition research or updating their knowledge will find the editors’ introductory chapter on past and current issues in the field particularly useful.