Circulating concentrations of B-type natriuretic peptide (BNP) and the N-terminal fragment (NT) of its prohormone (proBNP) are related to cardiac function and have emerged as clinically useful tools for the diagnosis of heart failure and for the estimation of prognosis in patients with heart failure and acute coronary syndromes. Recent studies have also convincingly documented that both BNP and NT-proBNP are powerful, independent prognostic indicators in patients with stable coronary artery disease. The associations are strongest for the end-points of death and heart failure, whereas the association with cardiac ischemic events is weaker or nonexistent, after adjustment for confounding factors. Importantly, BNP and NT-proBNP appear to provide incremental prognostic information to conventional risk factors, including markers of ventricular function and ischemia. Data documenting that BNP or NT-proBNP measurements can be used to guide treatment decisions in patients with stable coronary artery disease are still lacking.