Today, the knowledge concerning clinical reasoning is advanced enough to translate into curriculum interventions such as an integrated curriculum, in which science theory and clinical practice can be interwoven effectively. However, the interpretations of what integration means differ and the purpose of this study was to elicit how students understand integration. This study was carried out using an interpretative perspective. Medical students, in their 2nd year of study, were asked to apply basic science knowledge from all previous courses to clinical cases in an examination. Subsequent to the examination, focus group interviews were conducted. The interviews were audio recorded, transcribed and analysed by the use of qualitative content analysis. The analysis revealed how students comprehended integration: as the creation of wholeness, as relating new knowledge to core concepts, as reasoning, as application and as collaboration between teachers. The five categories were linked to three dimensions: intra-personal, inter-personal and organizational, each of which resonates with different theories of how expertise is developed. The outcome of this study adds to our understanding of how students conceptualize integration. The categories of 'integration' drawn out by the study are helpful in promoting further discussion of how eliciting students' own reports of cognition and may help the ongoing design of curricula by putting students at the center of the curriculum design process.