Since the discovery of atrial natriuretic factor in 1981 by de Bold et al, there has been tremendous progress in our understanding of natriuretic peptides (NPs). Recently, testing for brain-type NP (BNP) and its amino terminal cleavage equivalent (NT-proBNP) has been rapidly adopted in clinical medicine for numerous indications, including the diagnosis and exclusion of heart failure (HF). In this regard, logical application of BNP or NT-proBNP testing may not only reduce healthcare costs but also potentially reduce adverse clinical outcomes. With respect to this fact, the potential importance of the concentration of the NPs for prognosis and the response of BNP or NT-proBNP to therapeutic intervention in terms of clinical events has been demonstrated. On the basis of these observations it is reasonable to expect that concentrations of these peptides might be useful for the management of patients with HF, acting as a gauge of therapeutic accuracy and/or stability of disease. Besides HF, the prognostic utility of NPs has been explored in other settings, particularly in ischemic heart disease and those conditions that lead to right ventricular dysfunction.