Legacy used bookstores represent a distinctive and underexamined form of urban cultural heritage. These small-scale, independent businesses embody layered histories of literary circulation, community formation, and spatial memory. However, compared to the well-documented resurgence and increasing scholarly attention devoted to independent new bookstores as retail and community spaces, traditional secondhand bookstores remain significantly underrepresented in both practice and research. This thesis investigates the evolution, cultural significance, and preservation challenges of Philadelphia’s legacy used bookstores, tracing their development from the colonial period through the twenty-first century. It traces three detailed case studies through archival research into newspapers, city directories, and government documents, as well as GIS mapping, on-site observation, and interviews. These case studies demonstrate how used bookstores function as living archives, third places, and enduring expressions of living heritage. Situating used bookstores within broader processes of urban transformation, the study identifies the vulnerabilities they face amid rising rents, shifting consumer habits, redevelopment pressures, and marginalization within preservation discourses. It advocates for values-centered preservation strategies that recognize the cultural, social, and economic meanings embedded in these spaces, proposing adaptive approaches to sustain their continuity and relevance. The proposed strategies include enhancing community-engaged documentation, forming partnerships with cultural organizations, securing institutional tenancy models, and promoting inclusive legacy business programs that broaden the recognition of long-standing, often overlooked businesses such as used bookstores. Although grounded in Philadelphia, the findings offer broader insights into preserving small-scale, community-rooted businesses as vital components of contemporary urban heritage.