Natriuretic peptides have emerged as important candidates for development of diagnostic tools and therapeutic agents in cardiovascular disease. The family contains of three major peptides-ANP, BNP, CNP-that participate in cardiovascular and cardiorenal homeostasis. Each of these natriuretic peptides binds differentially to specific receptors that signal through different mechanisms. They are cleared enzymatically by neutral endopeptidase as well as by receptor-mediated endocytosis. Because of its fast induction and specific expression in overt heart failure, BNP seems the most promising natriuretic peptide. It is predominantly synthesized in the cardiac ventricles, released as pre-proBNP and then enzymatically cleaved to BNP and the N-terminal portion of BNP(NT-proBNP). Blood measurements of BNP and NT-proBNP have been shown to identify patients with LV dysfunction. This review focuses on the physiology of natriuretic peptides as a group and brain natriuretic peptide in more detail, its structure and regulation as well as its effects at the cellular level.