This article presents an action research project conducted in a Swedish compulsory school. In the project the participants explored ways of identifying actions to improve in the practices of a professional learning community in order to develop teaching. This is important for participants in such communities, since the outcome of developed teaching is challenging to achieve. The exploration is guided by practice theories and is based on three practices: teachers' peer observations of teaching, teachers' planning of these observations, and teachers' and a researcher's joint conversations based on the observations. By identifying actions in these practices and the relations between them, the findings show that how participating teachers formulated the direction of peer observations influenced the feedback that colleagues gave during observation practices, which in turn influenced both the input to and outcome of the conversations that followed these observations. The study not only shows "that" this happened, but also how and "why" it happened, as well as how it can be visualised. Overall, the findings clearly demonstrate what promoted and what prevented the teachers' professional learning and what needed to be improved.