Until recently in Japan, under the old administrative litigation system, typically 90% of plaintiffs in administrative cases (where citizens challenge the validity of the government's dispositions, such as in tax and restitution cases) lost. In response, scholars argued that the system was "unfavorable" and "dead." In 2004, the Administrative Litigation Act was finally modified so that plaintiffs would prevail more frequently. In this talk, Haruko Kato explores two questions: What did the low rate of plaintiff success reveal about the old system, and will the new Administrative Litigation Act lead to a higher success rate for plaintiffs?