AbstractClient involvement in modeling is expected to change mental models and thereby foster implementation of conclusions. Leading authors have pointed out that a lack of knowledge on the crucial elements of modeling interventions hinders accumulation of research results. There is no clear evidence for the effectiveness of group model building, and a conceptual model linking elements of the modeling process to goals is missing. We propose an integrative conceptual model, drawing on theories of persuasion (mental model change) and the influence of beliefs, attitudes, subjective norms and perceived behavioral control on actions. Our study builds on standard operationalizations and a body of research in social psychology. Data from seven group model‐building cases indicate that group model building changes attitudes, subjective norms and intentions. Conclusions for group model‐building practice are that participants often do not recognize mental model changes and that strengthening of participants' feeling of control needs special attention. Copyright © 2010 System Dynamics Society.