Max Planck Institute for Demographic Research is a research institute located in Germany. They study population change. They focus on understanding how and why the number of people living in a certain area changes over time. They look at things like death rates, birth rates, and migration to study what impacts population change. They use their research to figure out how to better plan services like housing, health care, and education to make sure cities, countries, and regions can take care of all the people who live in them.