 Mesenchymal stroma cells, master of science, are multi-potent stem cells found in nearly all tissues that possess self-renewal and differentiation capacities, migratory abilities, and can secrete protective factors and act as a primary matrix for tissue regeneration. Master of science derived from various adult and neonatal tissues have distinct cell biological properties, surface marker expression, proliferative capacities, in vitro and in vivo differentiation capacities within a variety of lineages, immune modulatory properties, and are influenced by extracellular and intracellular conditions. This article was authored by Bomes Stephanie, Casper Cornelia, Has Ralph, and others.