Published by the interdisciplinary design studio MODU, this "field guide" explores threshold spaces between the interior and the exterior. What are experiences between architecture and the environment? Where can the boundaries between the interior and the urban be drawn? What role does the climate crisis play in this? For their research and design projects, Phu Hoang and Rachely Rotem look at three major cities on different continents: New York, Rome, and Tokyo. MODU leaves behind the binary idea of inside and outside and rather understands architecture as an extension of the environment. Thus, it imagines a hybrid of urban space, architecture, and interior space. The book explores the different geographic locations and presents their own design projects. MODU is a Brooklyn, New York-based design studio working in architecture, urbanism, and interior design. It is led by Phu Hoang and Rachely Rotem and focuses on thinking architecture, urbanism, and the environment together. In 2017, they won the Rome Prize.