The purpose of this article is to describe how Lesson Study as second-order action research can be applied and how we planned to evaluate and improve course design, learners' progress, team members' roles and learning objectives of a 2-year university course for English as a Second Language teachers. The article describes the concept of a Lesson Study conducted in a course for teachers with a minimum of 3 years of teaching experience, rather than for students or undergraduates as in traditional concepts of the Lesson Study approach. PFL ('Pedagogy and Subject Didactics Programme') is a 2-year programme consisting of three seminars and five groups meetings in which the participants focus on the reflection of their professional practice in their specific school situation. All participants are required to plan, carry out and document their own action research project. The team provides input on action research and current topics in language teaching and learning, and advises participants. The methodology follows a mixed-method approach based on action research methodologies including questionnaires, interviews and observations. Analyses are conducted qualitatively and quantitatively. The article presents the concept of the project but not yet findings at this stage due to curriculum development and approval issues.