Deloitte Consulting

My experience here is in seeing Deloitte Consulting implement a very large software solution for my company, specifically using Siebel CRM. They brought in many resources (100+ consultants?), and were completely in charge of the project, which cost my company tens of millions of dollars.
Ultimately the project was very much a failure, in large part because it wouldn’t scale to meet the number of users that needed to use the system. For the first several weeks, the system simply would not work once more than a few hundred users were added, when normally we’d have thousands of users online at the same time. This really hurt our company terribly. The pain continued to a lesser extent for several months.
What’s worse, though, was their arrogance. Several employees of my company raised concerns about this scalability issue and were told by Deloitte management «don’t worry, we wouldn’t do anything to hurt your company. The project will move forward.» They wouldn’t even look at the objective data in a serious way.
I can’t comment on Deloitte Consulting’s track record as a whole, but they sure screwed us. I would strongly recommend not using them for large software implementations.