Concept mapping facilitates the externalisation and internalisation of knowledge by individuals during collaborative knowledge construction. However, not much is known about the individual and collaborative learning processes during collaborative concept mapping (CCM) in interdisciplinary knowledge construction. Premised on literature on collaboration scripts to scaffold the collaboration process, this study investigates the effect of an individual preparation phase prior to collaborative work on the epistemic and social processes of knowledge co-construction, as well as the degree of interdisciplinary knowledge integration in collaborative concept mapping. A total of N = 42 third year university students were put into one of the two experimental conditions: with individual preparation phase (WIP) and without individual preparation phase (WOIP). Students worked on a collaborative assignment to integrate interdisciplinary knowledge in collaborative concept mapping. Data for analysis was derived from audio recordings of the collaborative discourse in both experimental conditions. Chi-square test was conducted to investigate if there were significant differences between the effects of WIP and WOIP on the epistemological and social dimension. Findings showed that groups in the WIP condition showed significantly more verification, clarification and positioning statements in the epistemic dimension and also significantly more integration-oriented and conflict-oriented consensus building in the social dimension as compared to groups in the WOIP condition. On the degree of interdisciplinary knowledge integration, independent sample t-tests showed that there was no significant difference for concepts, domains and cross-links between the two experimental conditions. However, there was significant difference in types of cross-links for the CCMs in the WIP condition.