Machine learning and artificial intelligence are shaping the current and future practices in business management and decision making, thanks to the vast amount of available data, increase in computational power, and new optimization algorithms. The research at IEOR is at the forefront of this revolution, spanning a wide variety of topics within theoretical and applied machine learning, including learning from interactive data (e.g., multi-armed bandits and reinforcement learning), online learning, and topics related to interpretability and fairness of ML and AI. We are creating machine learning theory, algorithms, and systems for a broad spectrum of application areas, including financial technology, energy, recommendation systems, online advertising, business analytics, service systems, pricing and revenue management. Our faculty and students regularly collaborate with cutting-edge AI technology companies as well as local businesses, e-commerce companies, media houses, government, and financial firms. We work closely with colleagues in computer science and other engineering departments, and play an active role in the Data Science Institute.