The recent discovery that RNA can act as a catalyst, apart from carrying genetic information, has given a new dimension to the field of gene therapy and has come to act synergistically with antisense technology. Ribozymes can be used to down-regulate (by RNA cleavage) or repair (by RNA trans-splicing) unwanted gene expression involved in disease. Hammerhead ribozymes have been used extensively to down-regulate gene expression in many diseases such as viral infections and cancer. Group I intron ribozymes on the other hand, have only been tried to repair inherited mutations but hold great promise for the future. Peptide nucleic acids (PNAs) technology is another new technology, which is currently been tried to block gene or RNA function. Gene therapy protocols need significant improvements in order to be used routinely in patients and hopefully, these new players should prove valuable to identifying new therapies for several untreated diseases.