It's for EU nationals... rather than waiting in the queue for security and immigration, there is a dedicated line for Privium members (service provided by Schiphol). When one needs to go through immigration, the system uses your iris as identification, you go through the turnstyle and either have a dedicated security queue or get put to the front of the queue. For the Schengen gates (security closest to the BA check-in area), they just insert their card and go through.

It is really great looking... while I am waiting, people get through Privium in less than a minute. When I was going out on Thursday, I saw a line for the first time: all of 2 people!!! Very worthwhile if you travel at least once a week with no check-in luggage; literally reduces time at the airport to about 20-30 minutes.