Our group has pioneered molecular archeology of cancer approaches to study the evolutionary history and subclonal architecture of tumors. These approaches have significantly advanced our understanding of how cancer develops and evolves, how metastatic cancer spreads, and how resistance to therapy emerges. We use these existing molecular archeology of cancer approaches and develop novel ones, to perform large-scale pan-cancer studies of tumor evolution, as well as focused studies in specific tumor types, aiming to answer the key question: How do tumors evolve?