Based on over a decade of field investigations and research, this book starts with vivid examples from different levels, including households, courtyards, and neighborhoods, presenting the current state of the living spaces in Beijing’s historic areas, the evolutions, and daily lives of various groups in the 21st century in detail with simple, intriguing languages and abundant pictures. It delves into the pressing issues, the underlying causes, related policies, and practices. From a holistic perspective, it comprehensively analyzes aspects such as population, housing, public funding, renovation measures, business forms, and governance. It addresses six key issues and discusses four categories of boundaries, proposing suggestions for revitalizing historic areas and regenerating living spaces, advocating for balanced protection, bottom-line guarantees, and improved living conditions for vulnerable groups. At last, it introduces the exploration and ideas of the School of Architecture and School of Social Sciences, Tsinghua University, in their tracking study over an extended period, involving typical examples like the Shichahai area, Yandai Diagonal Street, Dashibei Hutong, and Xiaoshibei Hutong. This book offers valuable insights into solving fundamental challenges faced by historic areas, historical sites, and old neighborhoods in China.