Observations of clouds on exoplanets and Solar System objects including Earth confront our physical understanding of cloud formation, growth, transport, and radiative feedback. Recent observational characterisation with JWST of close-in gas giant planets, wide-separation planetary-mass objects, and isolated brown dwarfs has found strong evidence for cloud species in extrasolar atmospheres. This has enabled, for the first time, direct study of the cloud physics of planets beyond our Solar System. In addition, advances in our spatio-temporal measurements of clouds on Earth, current and upcoming missions to Solar System bodies including Venus, Titan, Mars, and Jupiter, and the advent of ground-based extremely large telescopes promise a wealth of observational data to test and refine state-of-the-art models. The time is now to develop a broad understanding of the physics of clouds encompassing the rapid discovery space of exoplanet observations that is grounded in our more detailed observational characterization of both Earth and Solar System planets and moons. In this conference, we will bring together observational, modelling, and experimental studies of clouds between the exoplanet, Solar System, and Earth communities to make advances at this crucial and timely interface.