We report on the results of a study to examine the global state of engineering education research on problem-and project-based learning (PBL). This paper has two major aims. First, we analyze a large collection of conference papers and journal articles to report on research trends in PBL, including in specific, leading countries. Second, based upon our analysis as well as a literature review of meta-analyses/syntheses of PBL literature, we propose a theoretical model for conceptualizing international research collaborations. Based on this model, we make recommendations for future initiatives, including multinational collaborations for research on PBL in engineering education