The Leibniz Institute for Tropospheric Research (TROPOS) pursues a clear and globally unique research profile, focusing on aerosols, which are tiny airborne particles, and clouds. Although they exist in minimal quantities, aerosols are vital components of the atmosphere, as they play a key role in regulating the Earth’s energy, water, and trace substance balance. Human activities can alter the properties of these highly dispersed systems, directly and indirectly affecting humans. This can happen both through the health impacts of inhaled particles and droplets, as well as through regional and global climate changes.