Recent advances in both software and hardware opened a new horizon of robotics: artificial intelligence discovered dynamic motions in simulation and hardware became powerful enough to execute human-level stunts. However, the current state-of-the-art robots are yet far from operating in the real world due to lack of agility, robustness, efficiency, and safety. My research aims to develop intelligent legged robots that can walk and navigate robustly to work in the real world. It includes novel deep learning algorithms, automated environments, scalable learning pipelines, and sim-to-real techniques. In the long term, I plan to develop robotic companions in our home and working environments that can change how we live, work, and play.