Two key qualities that I found to be helpful during DD are having an appreciation for cultural differences and being able to adequately manage politics. In dealing with organizations operating across different geographies, taking the time to understand the culture and common practices of the individuals you are connecting with, puts your discussions into perspective. It also helps in understanding the “why” in decision-making.
With respect to politics, especially in matrix organizations, this could be of significant importance. Being able to manage clashes of opinion between different functions and encouraging full transparency within the deal team will definitely make the long nights of working through diligence worthwhile. Instead of focusing on the differences, developing mutual milestones may eliminate some of the challenges.