To independently solve complex problems, such as a mathematical modelling problem, students can use metacognitive strategies to overcome obstacles and to ensure a smooth working process. Therefore, it is important for teachers to have knowledge on metacognition on the one hand and perceive and interpret the students’ (lack of) use of metacognitive modelling strategies on the other hand. In this chapter, we analyse the development of 52 pre-service teachers’ knowledge and noticing competencies for teaching mathematical modelling regarding students’ use of metacognitive strategies as well as the relationship between the two aspects. While the pre-service teachers’ knowledge regarding metacognition significantly improved during a modelling seminar, pre-service teachers’ noticing competencies barely changed. A correlation between both aspects (r = 0.38***) could be demonstrated.