Imaging of intracranial vascular structures and pathology has become more complex in the recent decade and involves multiple modalities, including conventional endovascular techniques (catheter angiography), magnetic resonance angiography (MRA), and computed tomographic angiography (CTA). Vascular malformations may be characterized physiologically as high or low flow, a determination that can dramatically affect treatment plans. Further characterization of high-flow vascular malformations in the brain is made based on complexity and drainage patterns of the malformation itself. Imaging of aneurysms has been shown with MRA, CTA, and conventional angiography, but the controversy still exists as to when and how to use these modalities in various clinical settings. The purpose of this chapter is to briefly review the types of intracranial vascular malformations, discuss the preferred methods of imaging in each case, and attempt to provide a rational approach to imaging the intracranial vascular structure and pathology with techniques available in 2007.