Despite the growing popularity of action research, bridging the gap between data collection and reflective data analysis still lacks a well-developed methodology. As a supplement to the traditional action research procedure for language teaching, I adopted a method called expansive visibilization (EV), which has the potential to be a reflective stimulus that facilitates the reflection of action researchers. EV was originally proposed by Engestrom (1999a) to help workers better understand and improve their workplace activities. I describe two EV sessions. The participants were two college and high school EFL teachers in Japan. Each went through the crucial second stage of EV. The participants first explained the daily contradictions that they faced when teaching. Subsequently, I asked them to draw a triangular diagram of their teaching and explain their teaching again using the diagram. I compared their explanations before and after use of the diagram. EV seemed to have changed the nature of the first participant's reflection, but not that of the second. This contrast demonstrates both the feasibility and limitations of EV as a supplement to conventional action research. (Contains 4 figures and 6 notes.)