I propose to investigate a new research frontier on spin physics at the boundaries (surfaces) of materials with strong spin-orbit interaction (SOI). Although the properties of these materials have been studied for more than half a century, researchers are just starting to grasp the richness of SOI phenomena that occur at them. SOI leads to surface and boundary states with unusually large spin splitting in simple heavy elements. It can also produce a nontrivial topology in band insulators that brings about metallic surface states with exotic spin textures that are protected by time reversal symmetry.Despite their fundamental and technological interest, information on the nature of charge transport at such states is scarce, while spin transport remains unexplored. I plan to use our cutting-edge expertise on all-electrical lateral spin injection and detection methods to unravel the spin dynamics in them, providing a wealth of information that could not be otherwise obtained. A comprehensive set of objectives will include material integration with ferromagnets and insulators, and innovative devices and measurement protocols. My team will gather information on injection, accumulation, scattering and relaxation processes of spins in the surface and boundary states. Complementary experiments will focus on current-induced spin-torque on a contacting ferromagnet and will address the question of whether spin-split metallic surfaces can enable spin information processing when deposited onto semiconductors.This is a highly challenging project, with a strong interdisciplinary nature across physical and material sciences that will open new avenues for the realization of exotic states of matter such as axions and Majorana fermions. While the research program is driven by the quest for fundamental understanding, new directions for applications could emerge from our basic science results.