Regenerative medicine is an emerging discipline that focuses on regenerating new body tissues through either transplantation of new cells or re-growth of existing cells. At Cedars-Sinai, our focus is on reprogramming old cells back in time to a powerful state from which they can regenerate any tissue of the human body. They can also be used to model human diseases in a petri dish. Finally, they may eventually be used for “personalized medicine,” where each patient at Cedars-Sinai has his/her own stem cells for therapy and drug testing.