Stem cells isolated from various sources have been shown to vary in their differentiation capacity or pluripotentiality. Two groups of stem cells, embryonic and adult stem cells, may be capable of differentiating into any desired tissue or cell type, which offers hope for the development of therapeutic applications for a large number of disorders. However, major limitations with the use of embryonic stem cells for human disease have led researchers to focus on adult stem cells as therapeutic agents. Investigators have begun to examine postnatal sources of pluripotent stem cells, such as bone marrow stroma or adipose tissue, as sources of mesenchymal stem cells. The following review focuses on recent research on the use of stem cells for the treatment of cardiovascular and pulmonary diseases and the future application of mesenchymal stem cells for the treatment of a variety of cardiovascular disorders.