A large part of civil society in Japan, and migrant support groups in particular, has been described as apolitical and service oriented, being strong in generating social capital but weak in advocacy or lobbying politics. Developments preceding the 2009 reform of immigration policies in Japan call for qualifying this assessment. While the majority of migrant support groups are active on the local level, some have formed a national umbrella organization that has formulated policy proposals, acted as an external advisor in the policy-making process and built networks with foreign governments, international organizations and NGOs. They have engaged in agenda setting and influenced the way in which migration and NGOs themselves are framed in the Japanese mass media. This I will show in a case study on advocacy organizations involved in the recent reform of Japan's Technical Intern Training Program (TITP) for foreigners. By focusing on a political process rather than a set of organizations, this paper not only observes transnational advocacy networks in the making, but also gives an accurate evaluation of their political impact. Migrant advocacy organizations informed an international public and were able to change the attitude of other political actors and interest groups and as a result tipped the scales in the policy-making process.