What is the extent to which various grammatical levels – from features through subjecthood through cleft layers – reuse and reemploy certain structure-building operations? In this volume, organized in terms of successively expanding domains, leading contributors report research into the complex edifice of grammatical structure of human language that one might liken to the terraced layers of a ziggurat. Following the heuristics of reverse-engineering, the chapters in this collection draw on theoretical and experimental analyses from Taqbaylit Berber to the sign language Cena, from the Romance language family to the Semitic family, in a kind to ‘reverse-architecture’ effort to understand the modes that compose multiple planes of morphosyntax. The volume, presented to honor the work and influence of Ur Shlonsky within linguistics, is aimed at a readership accessible to advanced undergraduates as well as specialists placed at distinct vantage points.