Tuberculosis (TB) is a completely curable disease, yet over 1 million people die from TB every year. One of the major challenges is to ensure that patients complete a full six-month course of antibiotics, which is required to make a full recovery. Using 99DOTS, patients reveal unpredictable hidden phone numbers whenever they dispense medication from a blister pack. They place free calls to these numbers to report that drugs are dispensed and taken. Patients who miss doses receive automated reminders, as well as targeted follow-up by care providers. In a close collaboration with the government and other organizations, 99DOTS has already reached tens of thousands of patients across India. By using simple yet innovative technology, we can help to ensure that every patient makes a full recovery from TB.