In nature, groups of thousands of individuals cooperate to create complex structure purely through local interactions -- cells, ants, bees, fish. Even though each individual has limited ability, as a collective they achieve tremendous complexity. What would it take to create our own artificial collectives of the scale and complexity that nature achieves? Our group is interested in understanding and engineering self-organizing swarms, where large numbers of relatively simple agents cooperate to produce complex collective behavior. We design and build novel bio-inspired robots and swarm algorithms, focusing on the combination of embodied intelligence and collective intelligence. We also study self-organization in nature, in collaboration with biologists. Our work spans Robotics, AI, and Biology.