Team-teaching between a Japanese teacher of language (JTL) and a native-English speaker assistant language teacher (ALT) has been widely implemented in English-language classrooms in Japanese schools for more than 20 years under the Japan Exchange Teaching Program (JET) launched in 1987. This study focuses on the classroom roles and responsibilities of these two types of teachers. The purpose of this study is to investigate two specific cases at schools in order to "localize" the national policy formulated in 2002 by the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT). The author aims to interpret this policy by means of a small qualitative "collective case study", rather than examination of a large amount of data from many schools. In examining how national policy is implemented in actual classrooms, this article triangulates data from observation of two classrooms in two different schools and interviews with the team-teachers. Although the national policy advocates equality in the team-teaching partnership, the two cases investigated clearly illustrate unequal practices. In contrast to national policy guidelines, this small-scale case study has revealed an unequal relationship between team-teachers at the local level and the extent to which local Japanese teacher intervention is necessary in classroom exchanges.