Comment: Ask for ROI Estimates (Score 4, Insightful) 298
Ask for ROI estimates instead of (or as well as) priority estimates. This won't work in every environment, but where it works, it can have a lot of upside.
I put it in play at a company where the engineers worked directly with marketing. One of the marketing guys was a pure sociopath -- lied about his priorities every single time, regardless of the upside for the company, just to keep his numbers up. After one particularly expensive project that generated about enough revenue to cover the electricity for the coffeemaker, I asked him for an estimate of ROI on the next project.
As it happens, he was actually a pretty sharp analyst, and he gave me some really accurate figures. They were low, and he acknowledged that his new project wasn't really high priority compared to the other things on the plate. He didn't even seem upset about it -- once he had run the numbers, he couldn't deny reality. It was the numbers' fault, not mine.
As noted above, this obviously won't work in every situation. When it does, however, it is quite effective. It also has some significant upside for marketing the IT department internally. If you keep track of the estimated ROI figures, and follow up for actual figures, you can make a clear case that IT is a profit center, not a cost center (as it is often perceived).