I read something in a magazine article about this subject. It said if you like the fabric buy 1 yard. If you really like it buy 2. If you find you can't live another minute without having it buy 3 yards. This is funny but still doesn't answer the question. I don't really know the answer. I usually buy 1 yard, if its on sale, I may buy more. If you decide to make a certain pattern, it may only call for 3 or 4 fabrics and you may not have enough, then you get to go back to the quilt shop! How awful!