Bread is an essential food consumed worldwide. Bread rapidly loses its desirable texture and flavor qualities associated with freshness through a process known as staling. The shelf life of bread is limited by this staling leading to economical losses in the range of one billion dollars per year. There are a number of mechanisms thought to be related to the staling process, such as water migration and redistribution, starch retrogradation, and gluten transformation. In this review, roles of water and water migration on bread staling are summarized and discussed.