Development of high-throughput methods for protein production is one of the most urgent issues to be addressed in the post-genome era. Recently we have succeeded in constructing a novel translation system, reconstituted in vitro from purified protein components involved in translation, called the PURE system. The PURE system is capable of synthesizing submilligram amount of protein per hour. The protein products are easily purified within one hour by the removal of the tagged translation factors using affinity chromatography. The PURE system will provide the possibility of efficient production of labile products.