IT organizations use strategic IT/IS benchmarking to assess their performance and identify starting points to improve IT strategy, processes, or operations. However, recent studies report that they are often unable to translate benchmarking results into action and therefore do not gain performance improvements. Research has not yet offered explanations for this discrepancy. Consequently, this study has two objectives: First, we want to understand what factors impact a successful strategic IT/IS benchmarking. Second, we want to determine how knowledge of these factors can be translated into a model for explaining the success of IT/IS benchmarking. We use a qualitative research design, analyzing three cases from different industries. We found that trust, participatory leadership style, methodological transparency, and top management support are causal for stakeholder commitment. The latter, together with management support, generates willingness to act. In turn, willingness to act and the benchmarking’s integration into the strategic planning process are factors explaining the success of benchmarking. We show that for benchmarking instruments, databases, and processes, methodological excellence is a necessary but not sufficient condition for benchmarking success. Therefore, we recommend that executives establish a systemic environment assuring management support and a high level of stakeholder participation fostered by a participatory leadership.