Plant growth and productivity are greatly affected by various stress factors such as drought, high salt, high aluminum, cold and hot temperatures, or short seasons. Drought tolerance improvement is probably one of the most difficult tasks for the cereal breeders. The difficulty comes from the diversity and the unpredictability of drought tolerance strategies developed by the plant that may be targeted and used as a selection criteria. In several cereal species, genetic maps have identified chromosomal regions controlling some traits related to drought stress response. Once genes are identified they may be transferred such as dehydrins produced by plants during drought or low temperature stress, abscisic acid (ABA) and the ABA response complex from barley to protect against dehydration stress and glycine betaine to improve tolerance to salt and cold.