This study attempts to examine the differences in the collaborative activities between the Turkish -contracting firms that are listed as the "Top 225 International Contractors" by Engineering News Record (ENR), according to their international revenues, and other large contracting firms that are not on this list. For this purpose, 30 large-scale Turkish general contracting firms, including 15 listed by the ENR, have been examined in terms of their collaborations during the innovation process as well as the levels of significance for the sources of information that serve as the means of " sources of innovation". Results show some remarkable differences between the top-listed firms and other largescale contracting companies. The levels of importance indicated for the collaborations made with "universities and research institutions" and the sources of information "conferences, fairs and exhibitions" and "scientific/technical publications" show remarkable differences between the two groups of companies. Contractors who are not ENR listed are more active in making collaborations. While the number of collaborations is increasing in the timeline, both groups of contractors indicate the most important collaborations as "consultants, private R&D institutions" and "suppliers". Findings also show a decreasing interest against collaborations with universities. Finally, findings of the research are discussed in the context of innovation, expecting to contribute to international contracting firms in evaluating their innovation approaches to their competitive advantage.