Aerosols (both natural and anthropogenic) interact with clouds and precipitation in complicated ways and with large uncertainties. They not only change cloud/precipitation microphysical processes, but also modify precipitation through radiation and dynamical feedback. This session welcomes both observational and modeling studies that aim to reduce uncertainties in aerosol impact on precipitation. These can range from process-based studies of aerosol impacts on cloud microphysics, to ensemble simulations of precipitation systems and their responses to aerosol forcing, to model parameterization development leading to better representations of aerosol-precipitation interactions in cloud, regional and global models.