Abstract. The aim of our study was to gain insight into the research field of critical success factors (CSF) of enterprise resource planning (ERP) system implementation projects. Therefore, we conducted two literature reviews, more specifically systematic reviews of relevant articles in five different databases and among several international conference proceedings. Ultimately, we identified 320 relevant papers (144 single or multiple case studies, 118 surveys, and 58 literature reviews or articles from which CSFs can be derived). From these existing studies, we discovered 31 different CSFs for ERP system implementation projects. The top three factors identified are Top management support and involvement, Project management, and User training. However, most of the relevant papers focus on large enterprises. Only 37 papers explicitly focus on smaller and medium-sized enterprises (SMEs), which is clearly a research gap in this field.