Mesenchymal stem cells (MSCs) can be an important tool for treatment of kidney disease. Their action is mediated primarily through paracrine effects: following systemic administration, mesenchymal stem cells migrate to damaged kidney sites, where they produce an array of anti-inflammatory cytokines, chemokines and growth factors. These secreted biomolecules can prevent further tissue injury and degeneration, most probably through activation of resident renal stem/progenitor cells, that in turn take place in a cascade of events that eventually triggers regeneration of diseased tissue.