Among the many detrimental impacts from climate change, sea-level rise is one of the most damaging, costly, and devastating. Sea-level change poses particular challenges for coastal communities, and is becoming more prevalent in environmental law. Existing scientific literature about how sea-level change works can often be inaccessible to the people that need it. In addition, each coastal community experiences a unique combination of global, regional, and local factors that define sea-level change. This Article provides an overview of how sea-level change works and a repository of data tools available to the public, covering how sea level is defined, measured, and modeled, the processes that change sea level globally and regionally, how these processes have changed over time, and how to interpret the scientific uncertainty present in sea-level science. It then examines how regional and local processes determine sea-level change along the Florida coastline and provides an overview of historical, modern, and future sea-level rise there. The Article can serve as a reference for understanding the science that may come up in legal cases related to sea-level change, and the associated toolkit provides regionally specific information for understanding sea level throughout the United States.