In most office buildings, stairs are required fire exits and little more, often alarmed so that even if you want to use them, you can't. I have noted before that if stairs were designed with more care and flair, then people wouldn't take the elevators and escalators so much, saving energy and making people healthier. Mayor Bloomberg of New York has recently joined the party, with his Center for Active Design, promoting " greater physical movement within buildings for users and visitors."
They seem to get this in Copenhagen; I saw a lot of very architectural open stairs in office buildings. This one was the most dramatic, in an otherwise ordinary office building for the big accounting firm BDO.
I like how you can see the stair through the exterior walls from both the front and back.
It's located at the start of the new pedestrian and cycling bridge that leads across to the famous MVRDV residential building built out of old silos.