I pre-wash everything except pre-cuts (jelly rolls, charm packs, layer cakes). I use a gentle/slow cycle on my washer ando not have a problem with fraying even on the fat quarters. The fabric gets washed as I select it for a project not once it first comes home. I have a friend that washes all fabric as soon as it comes in her door and, therefore, it is always ready to go. I prefer my method as when I am ironing it (with starch), I review my selections and often times will change something out. I guess I just like playing with the fabric until it's time to cut it.