Diffusion Tensor MRI is now a mature in vivo imaging method that provides unique microstructural information about anisotropic tissues, such as brain white matter. Still, there are a number of artifacts and obstacles that have hampered the development of a quantitative "pipeline" for processing DTI data. Some of these will be reviewed. There is significant interest in developing a statistical framework for describing the variability of DTI data. To this end, some findings from our recent work on developing a tensor-variate normal distribution will be described.