In the post-genomic era, several plant species have been sequenced and massive genomic information is now available which contributed to expand the development of novel technical strategies for the study of additional levels of biological information of plant species. This book focuses on the ?omics? approaches together with systems analysis of several different plant species, which have revealed very interesting variations on the cellular responses at the protein, transcript and metabolite levels in response to changes environmental conditions. The volume covers recent technological advances in the area of ?omics? and synthesizes recent findings of the field of plant ?omics? and systems biology together along with techniques that can be applied for such studies.