Title: "Causality and the microstructure of spacetime"

Physicists are still searching for a complete theory of quantum gravity which would explain why spacetime is what it is, from the tiniest Planck scale up to the scale of our universe. I will describe attempts to generate such a "quantum spacetime" dynamically, starting from a small number of fundamental physical principles. Exciting new results reveal that requiring geometry to be causal at the very smallest scales plays a crucial role in obtaining quantum geometries that resemble our four-dimensional universe at macroscopic distances.