This chapter combines analytical findings of urban shrinkage and urban decline to map the geographic distribution of US census tracts that experienced both shrinkage and decline over the four-decade period covered by the Brown University Longitudinal Tract Database (LTDB). It examines the role of three common processes underlying urban shrinkage and decline such as: deindustrialization, suburbanization, and demographic change in relation to the patterns of shrinkage and decline. The chapter explains the patterns of coupled shrinkage and decline using existing urban theories. Bonding and bridging networks, collective norms, trust, social cohesion, and community homogeneity are used for investigating the importance of social capital in understanding patterns of coupled shrinkage and decline in the United States. The social capital model of neighborhood change postulates two constitutive components of social capital: socio-cultural milieu and institutional infrastructure. Intra-urban theories of urban shrinkage and decline are generally categorized into one of three schools of thought: ecological, subcultural, or political economy.