Gene therapy is emerging as a potential strategy for the treatment of cardiovascular disease. A substantial, but controversial body of literature on gene therapy exists. Some supporting the belief that the clinical benefit of gene therapy has been expected to emerge too quickly and too easily, and that it is simply still too immature to deliver yet all its promises. Others believe that in the not too distant future gene therapy will become as routine a practice as heart transplants are today. Yet a third group regards it as a genie which has just started to partially deliver on its promises, but not as any good genie must do - without obvious effort, at a flash, just by asking. This review attempts to shed light on the issue by taking into account the differences in opinion, but focusing on evidence brought about by different experiences and clinical trials.