Founded in 2014, Thinx, Inc. makes absorbent underwear that can be worn during menstruation. But the feminine care market had seen virtually no innovation in half a century because of the taboo against discussing the topic of menstruation. As a result, the startup was competing against large incumbents like Procter & Gamble and Johnson & Johnson. Harvard Business School Associate Professor Rembrand Koning examines these strategic marketing challenges and discusses the importance of removing taboos and biases in order to bring innovation to the feminine care market in his case, “Thinx, Inc.—Breaking Barriers in Feminine Care.”