During the last decades, traditional learning environments have been criticised for not developing the prerequisites for professional expertise (H. Mandl, H. Gruber & A. Renkl, "Interactive minds: Life-span perspectives on the social foundation of cognition," pp. 394-412, Cambridge, UK: Cambridge University Press, 1996; P. Tynjala, "International Journal of Educational Research," 31, 357-442, 1999). To meet this criticism, educational approaches such as problem-based learning, project-based learning and case-based learning are being implemented to an increasing extent. Research also concentrates on the efficiency of these approaches in terms of students' learning outcomes. At the same time, classroom-based theories of learning (J. B. Biggs, "British Journal of Educational Psychology," 63, 3-19, 1993; M. Prosser & K. Trigwell, "Understanding learning and teaching." Buckingham, UK: SRHE and Open University Press, 1999) stress the importance of the investigation of subjective learning environments in order to understand the nature of these students' learning outcomes, for learning results are not a mere function of the learning setting because each student operates as a filter for the possible influence of the environment. However, most research on students' perception of the learning environment is conducted in predominantly traditional learning environments. The goal of our research was to investigate students' perceptions of the key design variables of a problem-based learning environment and if students perceive that they enhance learning. There are four research questions. First, to what extent do students' perceptions of a PBL environment match the theoretical assumptions of PBL? Second, do their perceptions differ as a function of the institutional context? Third, is there a difference in the perceptions of students between groups of first year and experienced students and between disciplines? Fourth, are there interaction effects between study phase and discipline? The results show that, in general, students value the key variables of the learning environment as powerful (i.e. enhancing learning). Also, the results indicate that students' perceptions of the learning environment in various institutional contexts differ significantly. In general, no distinctions were found related to students in different study phases. However, in terms of specific design variables, students studying in diverse disciplines showed significantly divergent perceptions. Finally, significant interaction effects were found between study phase and discipline.