I use multiple zipper pouches (Container Store / amazon.com) - one for in (black), one for read/review (green), one for travel (if I'm on the road - orange), one for @ office (pink), one for @ home (blue). I tried using individual folders, but they didn't work for me. I also tried one expandable file with dividers, but I found having a zippered pouch per category helped me *** do ***.