This volume presents the proceedings of the fifteenth West Coast Conference on Formal Linguistics held at the University of California, Irvine. This volume is a comprehensive representation of the papers presented at the conference in the areas of syntax, semantics and phonology, including a special focus on Native American phonology and syntax. Topics range from underspecification and natural classes to child language, with languages covered ranging from Basque to Navajo. This volume will be of interest to a wide range of linguists covering numerous special interests and fields.