Prereq: 15.809, 15.814, or permission of instructor. Hands-on course, using quantitative data to inform, make, and automate marketing decisions, including growth marketing, product design, pricing and promotions, advertising, and customer retention. Topics include creating metrics, randomized experiments, models for targeting, and analyzing launches. Features lectures, industry examples and guests, and data analysis assignments supported by in-class labs. Draws inspiration from the internet industry, but applications span many industries.