For several years, curricula based on the acquisition of professional skills were implemented in the training of teachers in Switzerland. The University of Teachers Education of Fribourg certifies students through assessments with complex tasks throughout the three years of training. Our research focuses on representations of students about this form of assessment, and more specifically on the meaning they attribute to this innovative process, which they rarely encountered in their previous school careers. The qualitative analysis reveals that this assessment method is perceived as meaningful, despite the fact that students often lack know - ledge of institutional assessment criteria. Furthermore, it suggests that learning achieved by students in this context raises questions as to the validity of the proposed tasks. Finally, we discuss its implications on the distinction between formative and summative assessment in the context of assessment of complex tasks.