Diffusion Imaging is a non-invasive MRI technique that is sensitive to the diffusion of water molecules. As molecular diffusion is restricted by cell structures (e.g., membranes), it allows inferences about the microstructural organization of the brain. Moreover, tractography reconstructions based on Diffusion Imaging can reveal patterns of structural connectivity in cortical and subcortical brain regions. Limitations on spatial resolution, sensitivity to the diffusion process (low b-values), and orientation sampling have limited its full potential to study the human brain until few years ago. Thanks to recent technological developments, a new generation of MR scanners are now available that are able of collecting data at much higher spatial and angular resolution, much faster and with stronger diffusion contrasts or stronger b-values. These technological advancements have opened the door to new and more sophisticated analysis procedures making diffusion imaging today a very fast evolving neuroimaging field.