$\theta_{13}$ and Beyond

I will briefly review the current status of neutrino oscillation and highlight the open issues. The current generation of neutrino experiments Double Chooz, Daya Bay, T2K and NO$\nu$A have started to probe $\theta_{13}$ and soon will deliver a first measurement. However, they can not test the mass hierarchy or study leptonic CP violation, therefore even larger facilities are needed. I will present the underlying physics and the various different proposals in detail.