Theta-13 Measurements

The current precise measurements of $\theta_{13}$ originate from reactor anti-neutrino disappearance measurements Double Chooz, Daya Bay, and RENO, as well as from accelerator neutrino appearance experiments MINOS and T2K. In this talk I will cover the experimental results and describe how we went from recently unknown value of this mixing parameter and suddenly ended up with a very precise quantity. I will also describe the standard neutrino oscillation framework and the role that $\theta_{13}$ provides as a critical input for experiments planning to measure CP-violating phase $\delta$ and the neutrino mass hierarchy.