Several risk stratification scoring systems have been developed that incorporate information from the history, physical examination, electrocardiogram, and occasionally the initial cardiac marker results. The Goldman algorithm, ACI-TIPI, neural networks, and the TIMI risk score can all help risk stratify patients with potential acute coronary syndrome but none of them is able to identify a cohort of patients at less than 1% risk who may be safe for discharge from the ED. The GRACE and PURSUIT risk scores all help stratify patients with unstable angina but have no proven benefit in cohorts of patients with undifferentiated chest pain. This chapter reviews the various scoring systems and the evidence basis for their use in the appropriate patient population.