This case study discusses the chain of events surrounding the delayed diagnosis and treatment of a patient with tuberculosis. The author uses the details of the case to illustrate the many systems problems that ultimately contributed to the error such as poor continuity, lack of communication, and multiple handoffs in care. The discussion includes potential strategies to prevent similar poor outcomes. This article is part of a special collection entitled "Quality Grand Rounds," a series of articles published in the Annals of Internal Medicine that explores a range of quality issues and medical errors.