In biology, function arises from structure. My research is focusing on understanding the principle and mechanism of biological macromolecules through detailed structural visualizations. Distinct from most of the other structural biologists working with purified macromolecules, I use electron cryotomography (ECT), the highest-resolution cellular imaging technique available, to resolve the native structures and assemblies of macromolecular machines directly inside cells as they are conducting functions. As a biologist with a background in engineering, I also continue to optimize the ECT technology to enhance its power and reach, including inventing new cryogenic super-resolution light microscopy methods to guide ECT for target specificity, and creating new sample preparation procedures for target accessibility in previously not imageable, thick samples. Together, my research marries biology and engineering to expand the boundaries of understanding biology from a structural perspective.