Patterns of Sounds describes the frequency and distributional patterns of the phonemic sounds in a large and representative sample of the world's languages. The results are based on UPSID (the UCLA Phonological Segment Inventory Database), a computer file containing the phonemes of 317 languages selected on the basis of genetic diversity. The book contains nine chapters analysing the UPSID data, as well as fully labelled phoneme charts for each language and a comprehensive segment index. Questions of the frequency and co-occurrence of the particular segment types are discussed in detail and possible explanations for the patterns observed are evaluated. The book is thus both a report on the research into phoneme inventory structure that has been done using UPSID and a resource that provides the reader with the tools to extend that research.