Gene therapy has become a significant issue in science-related news. The principal concept of gene therapy is an experimental technique that uses genes to treat or prevent disease. Although gene therapy was originally conceived as a way to treat life-threatening disorders (inborn defects, cancers) refractory to conventional treatment, it is now considered for many nonlife-threatening conditions, such as those adversely impacting a patients quality of life. An extensive range of efficacious vectors, delivery techniques, and approaches for developing gene-based interventions for diseases have evolved in the last decade. The lack of suitable treatment has become a rational basis for extending the scope of gene therapy. The aim of this review is to investigate the general methods by which genes are transferred and to give an overview to clinical applications. Maximizing the potential benefits of gene therapy requires efficient and sustained therapeutic gene expression in target cells, low toxicity, and a high safety profile. Gene therapy has made substantial progress albeit much slower than was initially predicted. This review also describes the basic science associated with many gene therapy vectors and the present progress of gene therapy carried out for various surface disorders and diseases. The conclusion is that, with increased pathobiological understanding and biotechnological improvements, gene therapy will become a standard part of clinical practice.