Researchers have been investigating cell-based therapies for treating Parkinson’s disease (PD) for some time now, using a variety of materials and methods. Two approaches have been to implant dopamine-producing cells or to induce cells already in the brain to become dopamine-producers. We asked Dr. Roger Barker, Professor of Clinical Neuroscience at the University of Cambridge in the United Kingdom, to summarize what has been learned so far and based on that, to give his perspective on where the field may be headed. The field is still in the experimental stages, and he cautions about what people with PD should ask when considering entering a clinical trial of cell-based therapy and what they may expect in terms of symptom management and disease progression.