This Book is a Prologue to the River Friend series of small books and is intended mainly for reference and as a picture guide to some common aquatic plants. Unlike the other books in the series, which con­centrate on a particular riverine aspect, this book shows what some common British water plants look like, with colloquial and scientific (Latin) names, as well as a glossary of terms and bibliography for further reading. In the series we have endeavoured to minimise the use of scientific terminology wherever possible. Inevitably there will be a few terms unfamiliar to some readers, so we encourage you to jump into the glossary on page 20 of this book for clear definitions of riverine and riparian terms used throughout the series.