Notice the position of the baby relative to mom’s breast.  The baby is slightly under the breast and her top lip is aligned with the nipple. Mom waits for the baby to open wide.  When latched correctly, baby’s top lip barely covers the nipple.   See “Claire’s Breastfeeding Story” for more detail about this video clip.

http://www.youtube.com/watch?v=k9YroD7JgbQ