Activities fall into four categories: cell and module research and development, reliability and scaling, manufacturing, and deployment. The tandem PV field is currently positioned at the intersection of cell and module R&D, and reliability and scaling. To meet the present International Technology Roadmap for Photovoltaic (ITRPV)-estimated timeline for perovskite/Si tandems to reach 2% market share, the 2% market share milestone would be reached in 2030.