For plant volatile organic compounds (VOCs) to be emitted, they must cross membrane(s), the aqueous cell wall, and sometimes the cuticle, before moving into the atmosphere. Previously, it was presumed that VOC movement through each barrier occurs via passive diffusion. Using Fick's first law, we calculated that to achieve observed VOC emission rates by diffusion alone would necessitate toxic VOC levels in membranes. Thus, we proposed biological mechanisms, such as those involved in trafficking other hydrophobic compounds, must contribute to VOC emission. I will present work on the identification of an active membrane transporter, facilitated diffusion across the cell wall and how cuticle thickness and composition mediate emission fluxes in Petunia flowers.