Network-building activities of PhD students are an important area of study in furthering our understanding of academic entrepreneurship. This paper focuses on PhD students' participation in network-building activities defined as mobility and collaboration, as well as own interest in and perceived grade of support for commercialisation from various levels of the university hierarchy. The results of a large-scale survey (of 1,126 PhD students at Linköping University, Sweden, 41% response rate) presented here show that the majority of PhD students are engaged in collaborations with external organisations, though quite few (one quarter) have spent a part of their PhD education outside their home university. PhD students from all faculties are on average interested in commercialisation and in favour of it. However, PhD students from the faculty of Health Sciences state that it is difficult for them to combine research and commercialisation. Furthermore, interest in commercialisation of research results is relatively lowest amongst those PhD students who are undertaking mobility placements at other universities, thus pointing to an experienced incompatibility of research and academic entrepreneurship.