Artificial intelligence powers every product experience at LinkedIn. Whether ranking the member’s feed or recommending new jobs, AI is used to fulfill LinkedIn’s mission of connecting the world’s professionals to make them more productive and successful. Although product functionality can be decomposed into separate components, they are beautifully interconnected, thus creating interesting questions and challenging AI problems that need to be solved in a sound and practical manner. Romer provides an overview of lessons learned and approaches LinkedIn has developed to address problems, including scaling to large problem sizes, handling multiple conflicting objective functions, efficient model tuning, and progress made toward deploying AI to optimize the LinkedIn product ecosystem more holistically.