In the past decade, our understanding of the standard model of cosmology has been shaped by constraints on Lambda-CDM from so-called Stage III surveys, such as the Dark Energy Survey. In the 2020s, a wealth of new data from Stage IV surveys – including the Roman Space Telescope – will enable us to either confirm or resolve tensions in the standard cosmological model and understand the physical origin of dark energy. In particular weak lensing and galaxy clustering statistics will provide key probes of structure, and therefore imaging surveys are vital parts of the infrastructure of survey cosmology in the 2020s. I will describe plans for Roman’s High Latitude Imaging Survey and discuss the new challenges that come with conducting a space-based NIR weak lensing survey, including my work modeling Roman’s detectors and developing new weak-lensing-based probes of cosmology.