Activity of transcription factors must be tightly controlled to regulate gene expression at a proper developmental timing and in response to environmental stimuli. Approximately 10% of plant transcription factors reside as precursor forms in the membranes, such as the endoplasmic reticulum and plasma membranes, and are activated by their liberation from the membranes to translocate into the nucleus where gene expression occurs. Studies in the past decade have facilitated our understanding of the roles of membrane-bound transcription factors in diverse biological phenomena, including abiotic and biotic stress responses, cell division, and hormone signaling. In this chapter we review the molecular and biological functions and the activation mechanism of membrane-bound bZIP and NAC transcription factors in Arabidopsis.