This systematic review study aims to describe the current state of the art with respect to fostering mathematical modelling competencies. The modelling literature was searched using six reputable electronic databases and a hand-search strategy. An in-depth analysis of 44 studies demonstrated that researchers have developed, applied, or recommended multiple strategies for fostering students’ and pre-service teachers’ modelling competencies. The study’s results indicate that the following aspects were of particular importance: 1) conducting training strategies and exposing students to modelling tasks, 2) supporting students’ and pre-service teachers’ metacognitive and psychological development, 3) using digital technologies, and 4) taking advantage of the strengths of different theoretical and conceptual constructs of modelling that were supportive for modelling competency development. The majority of the reviewed studies reported that the intervention strategies used to foster modelling competencies were encouraging but not fully satisfactory, since most participants were far from attaining expertise in modelling, even after the interventions. Future research should include more databases and different competency constructs in the literature search to overcome the survey’s shortcomings.