Recently, cyber transactions through the Internet have been rapidly expanding. Researchers have gradually begun to examine new legal problems with this new type of transactions. Japanese research, however, has been limited to problems governed by Japanese law and settled by Japanese courts. When using cyber tools , however , it is easy to engage in international trade as well as domestic trade. Cyber transaction studies should be focused upon problems involving conflict of laws and international civil procedure for international cyber transactions. So far, no Japanese researcher has begun these studies. On the contrary, in the U.S. and Europe, researchers have begun to examine problems in interstate or international cyber transactions and several judgments concerning these problems have been issued in the U.S. This program aims to research the situations in the U.S. and Europe and to introduce a new legal order into international cyber transactions in Japan.