My current research is about information in consumer markets. Information is transmitted between consumers and firms by advertising, consumer search, word-of-mouth between consumers, data brokers who sell information about consumers to firms, and by many other channels. Consumers get good or bad deals from sellers depending on (a) how much they know about the offerings of different firms and, conversely, (b) how much firms know about consumer preferences. The internet has been transforming both (a) and (b), allowing consumers to discover and evaluate products with greater ease and enabling firms to personalise prices and target their advertising. I try to formulate theoretical models of information flows, which aim to uncover which kinds of information help consumers and which kinds help firms (or both).