I saw the pillow in my chiropracter's office and bought the full size. It is way too thick on the ends and I am at a loss as to how one is supposed to sleep on your side using it that way. I then bought the petite, hoping that it would work better on my side, and so I could get it in my suitcase. It is better than the full size for side sleeping but not perfect. My neck still has problems in any position except on my back.