In reply to Domink Dengel.

If you float the secondary column right, it should remain fixed to the right edge of the screen. It's possible you'll need to move it before the other columns in the HTML too. The left column (primary) should be fine as it is.

If what you want is for the two sidebar columns to stay fixed so only the middle column can be scrolled, then you'd need to use positioning on those two columns and set each to position: fixed. I don't think this layout will work, if you use fixed positioning, though.