Book excerpt: Headless relative clauses have received little attention in the linguistic literature, despite the many morpho-syntactic and semantic puzzles they raise. These clauses have been even more neglected in the study of Mesoamerican languages. Headless Relative Clauses in Mesoamerican Languages constitutes the first in-depth, systematic study of the topic. Spanning fifteen languages from five language families, it is the broadest crosslinguistic study of headless relative clauses yet conducted. For most of these languages there is no previous descriptive or documentary material on wh-constructions in general, let alone headless relative clauses. Many of the languages are threatened or endangered; all are understudied. Each chapter in this volume constitutes an original contribution to typological and theoretical linguistics. The first chapter provides a comprehensive introduction to the varieties of headless relative clauses and their importance to the study of human language, while the other chapters are language-specific and follow a uniform format to facilitate comparisons and generalizations across languages. Through the collective work of a team of twenty-one scholars, Headless Relative Clauses in Mesoamerican Languages presents a clear and systematic introduction to relative and interrogative clauses in Mesoamerican languages.