The Voltage Dependent Anion Channel (VDAC) is the most abundant protein in the outer membrane of mitochondria. This strategic localization puts it at the heart of a great number of phenomena. Its recent implication in apoptosis is an example of the major importance of this protein and has created a surge of interest in VDAC. There is no atomic-resolution structure allowing a better understanding of the function of VDAC, so alternative techniques to X-ray diffraction have been used to study VDAC. Here we discuss structural models from folding predictions and review data acquired by Atomic Force Microscopy (AFM) imaging that allowed to observe VDAC's structure and supramolecular organization in the mitochondrial outer membrane. © 2008 Springer Science+Business Media, LLC.