To be successful in the digital economy a firm must find a source of 'market power', allowing it to charge prices in excess of its marginal cost. In this course, students will learn to formulate business strategies to overcome the zero marginal-cost problem. Topics to be covered include the economics of social networks, scale economies and learning in AI, creating customer lock-in, reputation as an alternative to regulation, and the composition of digital ecosystems. Students will also learn how to assess the implications of these business strategies for societal wellbeing.