I think you can have 1 WW tortilla so long as it follows the guidelines: "Tortillas, 100% whole grain, 3 grams of fiber or more per ounce, no trans fat" I found this in the FAQ sections at the top of the page under the updated list of Ph2 foods. I'm not sure how big the tortilla can be but I know they come in a range of sizes from 6"-12". I'm guessing the size is based on the fiber grams and you can tell which is O.K. from the nutritional info on the package. Hope this helps.