The study book presents modern theories of phonology at a high yet generally understandable level. It is primarily aimed at students of general and Germanic linguistics in their undergraduate and graduate studies, but it is also suitable for self-study. The eleven chapters each focus on a specific area of phonology, such as phonetic foundations, distinctive features, autosegmental phonology, syllable phonology, prosodic phonology, and optimality theory. Each chapter includes a series of exercises for further exploration.