Tribbles are fictional creatures in Star Trek. They are small, soft, and gentle, and producing a soothing purring sound. These traits are said to endear them to all who encounter them, with the notable exception of Klingons, who consider Tribbles to be "mortal enemies" of the Klingon Empire.
Roughly translated, if you don’t like someone, odds are, they don’t like you too. So don’t go around making enemies across your organization. Work on building friends and constantly improving relationships. At my university the Information Systems department used to be called “Computing and Systems Services,” so “CASS” was the acronym. But everyone across campus called the department “Fortress CASS” or “Fort CASS.” Needless to say, it wasn’t a popular department. My job has been to knock down the walls and build bridges over the moat to the rest of the campus.
You do that by “opening the kimono” and being transparent (no secrets). We became transparent by actively engaging the campus in information systems decision-making through a broad governance process. Asking clients what they want, and making it happen as promised. Do what you said you would do and get it done. It's not rocket science.
We have had our governance process in place for five years. Business decisions are made by our clients and we simply facilitate the process. We are like Switzerland. We are neutral about the business decisions as long they have fit, utility, and balance. Fit means the decision is aligned with strategic plan of the institution. Utility means the quantitative and qualitative benefits outweigh the costs and risks. Balance means you treat your IT projects like an investment portfolio that is appropriately weighted across the institution.
Combining this governance model with a robust project management culture has been key in building bridges and developing trust across campus. Building trust takes time, but eventually even Klingons and Tribbles can learn to trust each other.