No pre-washing for me, throw a completed quilt in the wash with a color catcher and regular laundry detergent, run through one cold water wash cycle and a double rinse cycle. Toss in the dryer on medium heat until nice and dry. If there is any shrinkage it just adds to the crinkley old-fashioned look of the quilt, which is fine by me since I make all of my quilts to be used (the crinkley the better) Is crinkley a real word?? :-)