Antisense therapeutic agents are now moving from the research laboratory to the clinic. The first generation of antisense drugs will be marketed before the new millennium. This promising new class of therapeutic agents will revolutionize the way that disease processes will be treated and perhaps even how we come to classify diseases. Antisense drugs are being used in a broad range of disease indications from viral infections, to cancer, to inflammatory diseases. The molecular targets range from viral transcription factors, and oncogenes, to cellular adhesion molecules. Many drugs are well beyond Phase I clinical trials, with the data on the safety and efficacy of these agents now being analyzed.