Because of their sessile nature, plants grown in a dynamic climate have evolved a range of adaptations that enable them to survive in various environmental stress conditions during growth and development. Plants respond to environmental stresses at both cellular and molecular levels by altering the expression of many genes via a complexity of signaling pathways. These pathways begin with signal perception and end with the expression of stress-responsive target genes. Ultimately, the selective upregulation of target genes leads to the alteration of physiological response so as to confer tolerance of the stress. In the signal transduction network, various regulatory and functional proteins function collectively to ensure survival of the plants. This chapter summarizes the methodology used to dissect gene regulatory networks involved in the response to osmotic stresses, such as drought and high salinity.