Tuberculosis is a devastating disease that infects one-third of the world’s population, leading to eight million new cases and three million deaths per year. The prevalence of this disease is largely due to the ability of Mycobacterium tuberculosis (the bacteria that causes tuberculosis) to evade destruction by the immune system. Normally, when bacteria invade the body, the human response system triggers specialized cells called macrophages to engulf and destroy bacteria. In the case of tuberculosis, M. tuberculosis succeeds not only in escaping annihilation, but is able to enter and live inside the very cells that are programmed to destroy it. Using yeast as a model organism, Emily Thi is studying and identifying the components of the arsenal that Mycobacterium tuberculosis uses to successfully infect and survive within human macrophages. Her research on M. tuberculosis proteins that disrupt normal macrophage function may lead to the identification of novel targets for drug and vaccine development, which could result in new strategies to combat this challenging disease.