This volume offers a broad and comprehensive examination of observational, modeling and theoretical aspects of coastal sea level science. The collection of overview articles provides up-to-date information on the causes of coastal sea level variability and change, contributes to better understanding of the influence of large-scale climate signals and open ocean processes on the coast, and addresses effects of waves, storm surges, and tides on extreme sea level and coastal flooding. Projections of long-term coastal changes and associated uncertainties are also proposed. The volume contributes to better identifying priorities for the development of an optimal and integrated (satellite and ground-based) coastal observing system and highlights present modeling and observing challenges for monitoring and predicting coastal sea level on daily to multi-decadal time scales. Previously published in Surveys in Geophysics, Volume 40, Issue 6, 2019The chapters "Concepts and Terminology for Sea Level: Mean, Variability and Change, Both Local and Global", "Forcing Factors Affecting Sea Level Changes at the Coast", "Sea Level and the Role of Coastal Trapped Waves in Mediating the Influence of the Open Ocean on the Coast", "Impacts of Basin-Scale Climate Modes on Coastal Sea Level: a Review", "Interactions Between Mean Sea Level, Tide, Surge, Waves and Flooding: Mechanisms and Contributions to Sea Level Variations at the Coast", "Uncertainties in Long-Term Twenty-First Century Process-Based Coastal Sea-Level Projections" and "Probabilistic Sea Level Projections at the Coast by 2100" are available as open access articles under a CC BY 4.0 license at link.springer.com