The pathophysiology of heart failure is complex, and the list of biomarkers representing distinct pathophysiologic pathways is growing rapidly. This article focuses on some promising newer biomarkers that have contributed to a better understanding of pathophysiologic mechanisms involved in heart failure but for which less data are currently available: osteoprotegerin, galectin-3, cystatin C, chromogranin A, and the adipokines adiponectin, leptin, and resistin. Despite the intriguing early information from these newer markers, none is ready for routine clinical use. Much additional study is needed to determine how these biomarkers will fit into diagnostic and treatment algorithms for patients who have heart failure.