The measurement of the neutrino mixing angle θ13 with reactor neutrino experiments

Currently running reactor neutrino experiments with a baseline of about 1 km have provided the first clean measurements of the third neutrino mixing angle θ13. This review summarizes their basic principles, performance and results. Emphasis is placed on a thorough description of the experimental techniques, including detection of the neutrino signal, determination and suppression of correlated backgrounds, and an overview of the systematic uncertainties that are relevant for a precision measurement of θ13.