This course offers an overview to a suite of tools, known as paleoclimate proxies, used to study past changes in the ocean and climate beyond the instrumental era. Paleoclimate proxies in marine sediments are based on the remains of marine organisms. The spatial distribution and biochemistry of these fossils contain information of past climatic parameters, such as seawater temperature, salinity, atmospheric carbon dioxide and more. This course covers proxy development, application and uncertainties, as well as inter-proxy and proxy-model comparisons.