Modular stair/ladder system by Arke. The product is from Italy. It can be purchase though Lowe's, Home Depot or directly from Arke. It can be assembled by a DIYer, but be prepared for some less than descriptive instructions. Customer service is a 8 to 5 M to F EST, so if you start on a weekend and get stuck you won't reach any one till Monday.

http://www.arkestairs.com/karina.php