The International Announcement of Opportunity for ISS utilization in the field of microgravity science was issued in the autumn of 2000. The international peer science-review process started in May 2001 and the international peer review meetings were held at NASA Peer Review Services in Washington for six panels of different fields. Then, the technical review and the program review by each agency followed, and the final review reports were sent to the Japanese applicants in January 2002. The author's experiences in these processes are described with some comments. Discussion is made on the conditions for a proposal to be highly evaluated.