Book excerpt: This book contains contributions by scholars working on diverse aspects of speech who bring their findings to bear on the practical issue of how to treat stuttering in different language groups and in multilingual speakers. The book considers classic issues in speech production research, as well as whether regions of the brain that are affected in people who stutter relate to areas used intensively in fluent bilingual speech. It then reviews how formal language properties and differential use of parts of language affect stuttering in English, and then compares these findings to work on stuttering in a variety of languages. Finally, the book addresses methodological issues to do with studies on bilingualism and stuttering; and discusses which approach is appropriate in the treatment of bilingual and multilingual people who stutter.