My research focuses on the emerging concept that tumours are complex, evolving ecosystems with dynamic crosstalk between cancer and normal cells. Understanding how genetically diverse cancer cells adapt to and manipulate their microenvironment is critical for deciphering drivers of cancer progression and evolution. To answer specific questions for a disease type, my team develops new approaches that are fusions of pathological image analysis, bioinformatics and ecological statistics. I will discuss how our study on spatial heterogeneity of immune response led to new appreciation of its clinical relevance in breast cancer within the context of clinical trials, and our recent progress on studying the relationship between microenvironmental diversification and lung cancer evolution in TRACERx.