Nuclear factor (NF)-kappaB is regarded as one of the most important transcription factors and plays an essential role in the transcriptional activation of pro-inflammatory cytokines, cell proliferation and survival. NF-kappaB can be activated via two distinct NF-kappaB signal transduction pathways, the so-called canonical and non-canonical pathways, and has been demonstrated to play a key role in a wide range of inflammatory diseases and various types of cancer. Much effort has been put in strategies to inhibit NF-kappaB activation, for example by the development of pharmacological compounds that selectively inhibit NF-kappaB activity and therefore would be beneficial for immunotherapy of transplantation, autoimmune and allergic diseases, as well as an adjuvant approach in patients treated with chemotherapy for cancer. Gene therapy targeting NF-kappaB is a promising new strategy with the potential of long-term effects and has been explored in a wide variety of diseases, ranging from cancer to transplantation medicine and autoimmune diseases. In this review we discuss recent progress made in the development of NF-kappaB targeted gene therapy and the evolution towards clinical application.