Since last September I have been reading as Wendy Wickham and her colleagues have braved management, clients, and everyone else in a major upgrade project. She summarizes, "I hope I NEVER have to do a project of this sort again.... Rushing major upgrades of mission critical systems may look glamorous but you can cause serious long-term damage. To the morale of the IT team, to the goodwill of the end user. And to the system itself if you have a partially finished product. It has taken months and they still have not recovered. No one's fault, but very preventable." The series of posts linked here constitute a detailed description of the project, an object lesson everyone should learn from.