The white matter of the brain consists of bundles of axons that are connecting the different grey matter regions in the brain. Diffusion MRI uses the Brownian motion of water molecules as probes into tissue microstructure, which allow us to tune the diffusion MRI sequence sensitive to more specific features of white matter as the fibre orientation, axon diameter and densities etc. In this talk I will present some of our recent work on probabilistic tractography on Anatomical Connectivity Mapping (ACM) that provides voxel wise measures of connectedness. Additionally, discuss via our Iterative Confidence Enhancement of Tractography (ICE-T) framework the path-length dependency effect in probabilistic tractography and that can influence network analysis. I will then shift to microstructural imaging and present our ActiveAx for extracting axon diameter and fibre density. We will discuss the challenges in designing biophysical models given our relative limited insight and understating of the true underlying microstructure. Finally, I will highlight new trends in sequence design and the features we can extract.