The reason why I used external IT consultants the first time was that I was short of development resources. I was in a situation in which I simply did not have enough staff to get the projects done.
ProData Consult, the consultancy house, has been working with TDC for many years now, and we have a framework agreement with them. However, the main reason why I choose to work with them is their competent staff, who do a great job in delivering the right resources - and delivering them fast. I often find myself in situations where I need IT competences four days ago - so things really have to move!
In my experience, ProData Consult is a very flexible consultancy house with a great many contacts and a giant network that allows them to find highly qualified IT resources very quickly. Their IT consultants are competent, committed and motivated. The consultants contribute fully, are very proactive and really add knowledge to our projects.