Mesenchymal stromal/stem cells (MSCs) have the potential to repair and regenerate damaged tissues, making them attractive candidates for cell-based therapies. Expanded and well-characterized MSCs have application in regenerative medicine and have been used in several clinical trials including treatment for osteoarthritis and other conditions. Here, we provide results of a comparative study of purified and expanded MSCs from adipose, bone-marrow, placenta, and umbilical cord involving determination of phenotype by flow cytometry analysis, cellular potency by quantitative assessment of mitochondrial function and immunosuppression, and cellular function by quantitative assessment of cell migration and proliferation. Our results show comparable phenotypic profiles, morphology, expansion in cell culture and adipogenic, osteogenic and chondrogenic differentiation. Potency measures of mitochondrial/immunosuppressive capacity and additional cellular function assays show differences suggesting biological advantages of umbilical MSCs.