This volume provides the most comprehensive treatment of phonological weight to date, bringing together traditional notions of categorical, rime-based weight and new developments in statistical prosodic phonology. The book demonstrates that while some systems treat weight as a simple (heavy vs. light) distinction, others treat it as a rich continuum of heaviness. Following an introduction to weight-sensitive systems in phonology, Kevin Ryan explores the range of phenomena that interact with prosodic weight. Chapters examine the analysis of scales in terms of prominence rather than moraic coercion; prosodic minimality in the context of larger prosodic constituents; syllable weight in metrics; and the relationship between prosodic end-weight and stress. Throughout, the analysis is based on a survey of weight systems both within and across the world's languages, which yields a number of valuable generalizations and points towards a universal theory of weight in human language.