ABSTRACT Ways of producing local systematic knowledge in social services have gained attention. In Sweden, individual-based systematic follow-up (ISF) has emerged as a way to follow-up on interventions and produce local knowledge. Practitioners are responsible for collecting and compiling as well as interpreting and taking action based on ISF results. This article aims to understand how knowledge is produced within the ISF practice by looking at when and how practitioners reflect on ISF results. The research was conducted within social service units providing non-institutional interventions for children and families in two Swedish municipalities, with experience from working with the models LOKE (Local Evidence) and FIT (Feedback-Informed Treatment). The material consists of 8 observations, 45 documents, and 21 interviews with family therapists, heads of units and departments, executive directors, and development officers. The findings show how individual and collective reflections are central in producing knowledge from ISF results and why conditions for reflection need to be organizationally facilitated. It is oriented towards sense making within the context of practitioners’ daily work in relation to their knowledge and experience. Collective reflection on ISF results, undertaken with colleagues or service users, suggests a co-production of knowledge. However, depending on the ISF model, certain perspectives become more or less prominent, for example the degree of service user involvement. This is important to take into account when choosing an ISF model to implement in practice.