My DH is a director in a company that employs a lot of people world wide. They have the same policy on references. However, he does give references for certain people. I think this must be done informally by a lot of people.
I just had lunch with my supervisor from my internship, as I am going to have to use her as a reference when I start looking for a new job in a month or two. I can't ask my current bosses, as they are being so nice to me, trying to think it will make me stay! They kind of know I am going to be paring down my caseload, so I don't want to cause any more stress.