A qualitative case study was conducted to triangulate student interviews, a teacher’s reflection report, and classroom observation data to understand how a local language course prepared Taiwanese administrative staff for international communication across working contexts in an international university. The findings firstly show that the teacher treated course planning as a teacher and student process of co-developing, co-moderating, co-revising, and co-managing learning resources and content. The teacher empowered the administrative staff by giving them the authority to select language targets for study that the staff thought would be useful to fulfil their job duties. Secondly, participation of the administrative staff was important in creating and managing language resources for international communication. The teacher used vocabulary and dialogue writing and speaking practices that were contextualised to the needs of the administrative staff. The targeted vocabulary was selected by the administrative staff based on gaps in their knowledge and was then used to co-construct dialogues that addressed scenarios the staff had previously encountered that necessitated the use of English with internationals. Thirdly, developing the course to address the administrative staff’s communication needs was a process of rebalancing teacher autonomy, learner autonomy, and course development. Both the teacher and the students perceived the course effective in encouraging practical changes in the administrative staff’s learning and use of English, which they mostly attributed to the non-formal nature of the course and the support from higher management. Implications for planning and implementing English language courses for international communication were drawn from the findings.