siRNA technology has not only greatly facilitated functional characterization of new genes, but also presented tremendous potential for becoming the next generation of blockbuster drugs. The technology has penetrated life science research in an extremely fast speed, thus providing a huge knowledge base for siRNA drug development. Significant technical progresses have been achieved over the past ten years towards the research and development of siRNA therapeutics, and several compounds have been put into clinical trials. This review would provide a summary of such progresses.