Though its tempting to cleanse one's closet of all pieces that haven't been worn in the past 2 seasons in order to create much needed space (if you live in or near the City), a glance through the September issues is a lesson in restraint.
Example: I have had this full, mid length, ocean blue, jade green and ivory skirt from Club Monaco since approximately 2004. When I first moved to the city to join Ann Taylor's buyers training program after college I remember it being one my very first splurges ($160 for a skirt is still a splurge in my book, by the way). The full fabric nips in at the natural waist and bows out subtly below. As trends and hem lengths have risen and fallen with moon, the skirt had moved further back in the wardrobe, taking a back seat to pencils, above the knee tweed minis, and tulip cuts. Flash forward to present day, and Marc Jacobs collection for Louis Vuitton has placed the full, mid length, ladylike skirt front and center. The treasure from 2004 suddenly is fresh and so happily still hanging in my closet. (The same story can be told about my Coach platform, 3 inch heeled penny loafers from 2006, which, with the addition of fresh soles at the local shoe repair, eliminate the need for Prada's 2010 version.)
Take care when closet purging, so that the inevitable fall binge does not leave you regretting your choices.