In this review we summarize the available evidence regarding the application of stem cell therapy for human cardiovascular repair, going over the principal concepts that will help us understand the present and future of this therapy: first the different types of cells available in clinical practice, second the delivery approaches, and third highlighting the most important clinical studies and their efficacy and safety results. In addition, we also speculate on the value of current clinical data to gain an insight into the mechanism of stem cell-based cardiac repair and to design clinical trials in the future.