Spin is a quantum property that plays an important role in magnetism, and there are proposals to use spin for quantum computing and “spintronics,” devices that combine electronic logic and magnetic storage. In general, spins in non-magnetic materials are not polarized, but I will describe optical techniques that my group uses to excite electron spin polarization and then monitor its dynamics and show how this data can be used to probe carrier drift and diffusion, spin-orbit effects and dynamic nuclear polarization.