What is the real world equivalent of "Consortium" in Dan Brown's Inferno?

Today I was reading Dan Brown's latest novel Inferno (Excellent novel btw) and out of the many bizarre things, I was most intrigued by the discreet organization called Consortium that provides its clients with discreet professional services (sometimes of questionable moralities). We can understand the actions of the famous three lettered organizations in each country (like FBI, NSA, etc.), but this seems beyond sci-fi.

Does such an organization really exist? Of course, Brown himself claims it positively at the beginning of the book:

'The Consortium' is a private organization with offices in seven countries.

But does anyone know the real name of this organization and what seven countries is it present in?