A cogent, freshly written synthesis of new and classic work on crosslinguistic influence, or language transfer, this book is an authoritative account of transfer in second-language learning and its consequences for language and thought. It covers transfer in both production and comprehension, and discusses the distinction between semantic and conceptual transfer, lateral transfer, and reverse transfer. The book is ideal as a text for upper-level undergraduate and graduate courses in bilingualism, second language acquisition, psycholinguistics, and cognitive psychology, and will also be of interest to researchers in these areas.