There is considerable interest in teacher collaboration across mother tongue and second language curricula. However, cross-curricular collaboration in reading strategy instruction has seldom been investigated. We report a two-year study involving collaboration between the French first language (L1) and English second language (L2) teachers in an intensive English as a second language (ESL) programme in Quebec, Canada, as they raised their own and their students' awareness of reading strategies. Findings from Year 1 revealed that while teachers broke some of the barriers of isolated teaching, cross-curricular connections were difficult to make as they were unfamiliar with each other's curriculum, and the L1-L2 strategy terminology was not uniform. In Year 2, we provided the teachers with tables showing equivalent terminology for strategies from both the L1 and L2 curricula and documented the process by which their awareness of both curricula facilitated collaboration, reading strategy instruction, and the development of a transferable pedagogical approach to teaching strategies. We found that the consistency of instruction strengthened learner awareness and autonomous use of reading strategies. We conclude that reading strategies provided a structure for mirroring instruction across languages. However, in order for teachers to collaborate, they need time, materials, and administrative support.