Working on different projects means dealing with people across several business units. These colleagues do not report directly to you, but they play a role in the success of the project and you need them to develop and prioritize tasks. By motivating them, explaining the importance of their contribution and being thankful for them, you can overcome these challenges. Implementing change and supporting colleagues through this is another key challenge. Usually people are afraid to change as it moves them out of their comfort zone. Processes, tools, methodologies, structures and tasks often change in the organization, so you need to be really sure you have strong reasons for the change (efficiencies, group standards, quality, control and so on).