The death of a woman during pregnancy, childbirth, or the year postpartum is a rare and tragic event. Unfortunately, it happens too often in the United States. Pregnancy-related deaths increased from seven deaths per 100,000 live births in 1987 to nearly 16 deaths per 100,000 live births in 2012. Maternal health experts actively search for answers about why the ratio of pregnancy-related deaths in the United States is higher than other developed nations, why it is increasing, and why the disparity by race/ethnicity is widening. State-level maternal mortality review committees – the gold standard for maternal mortality surveillance – have a critcal role in answering these questions. Maternal mortality review committee members serve as key stakeholders in prevention efforts. In order to accurately count and characterize maternal deaths, individuals involved in the surveillance process should familiarize themselves with key definitions in maternal mortality and how they are used in maternal mortality review.