We investigate scientific collaborations in China in the context of international collaboration on the basis of a co-authorship network (in the field of scientometrics),using Q-measures as indicators of internationalization in collaboration.The results show that a relatively small group of Chinese researchers is internationally active,and that most of them mainly form bridges between China and other countries.There is a clear dominance of three institutes,viz.ISTIC,Dalian University of Technology,and Henan Normal university.The main domestic broker for China is Liang Liming,whereas the main foreign broker for China is Ronald Rousseau.A small amount of international collaborations takes place outside the largest component of the network.