CERN LHC. The WZ production cross section is measured by the CMS experiment at the CERN LHC in proton-proton collision data samples corresponding to integrated luminosities of 4.9 fb−1 collected at √s = 7 TeV, and 19.6 fb−1 at √s= 8 TeV. The measurements are performed using the fully-leptonic WZ decay modes with electrons and muons in the final state. The measured cross sections for 71 < mZ < 111 GeV are σ(pp → WZ; √s = 7 TeV) = 20.14 ± 1.32 (stat) ± 0.38 (theo) ± 1.06 (exp) ± 0.44 (lumi) pb and σ(pp → WZ; √s = 8 TeV) = 24.09 ± 0.87 (stat) ± 0.80 (theo) ± 1.40 (exp) ± 0.63 (lumi) pb. Differential cross sections with respect to the Z boson pT, the leading jet pT, and the number of jets are obtained using the √s = 8 TeV data. The results are consistent with standard model predictions and constraints on anomalous triple gauge couplings are obtained.