This chapter summarizes a wide range of data collection efforts and spatial analyses used by various scholars to assess the impact of sea level rise on population and built environment, environmentally sensitive areas, and economic assets. The scholarly studies focus primarily on coastal cities and low-lying areas around the globe. The chapter includes a case study on how to disaggregate future population projections using ancillary data, evaluate the impact of sea level rise on future coastal development, and estimate the number of people potentially at risk if adequate policy measures are not put in place. This is followed by a discussion of data and methodological issues that limit such assessments, which are collectively used to inform adaptation and risk reduction strategies and policy-making as documented in the final section of the chapter.