Action research (AR) can be an effective form of ‘on the job’ training. However, it is critical that AR cycles can be appropriately recorded in order to contribute to reflection and learning. One form of recording is for coresearchers to keep a diary. We found no previous literature describing the use of diaries in AR in sub-Saharan Africa. We therefore use this paper to reflect on how diaries were used by district health management teams in the PERFORM project. We share five lessons from our experience. First, it is important to foster ownership of the diary by the people who are responsible for filling it in. Second, the purpose of keeping a diary needs to be clear and shared between researchers and practitioners from the very beginning. Third, diaries should be allowed to evolve. Fourth, it is a challenge for busy practitioners to record the reflection and learning processes that they go through. Last, diaries on their own are not sufficient to capture reflection and learning. In conclusion, there is no best way for practitioners to keep a diary; rather the focus should be on ensuring that an AR recording process (whether diary or otherwise) is locally owned and complements the specific practice setting.