CERN LHC. A measurement of vector boson scattering and constraints on anomalous quartic gauge couplings from events with two Z bosons and two jets are presented. The analysis is based on a data sample of proton-proton collisions at √s= 13 TeV collected with the CMS detector and corresponding to an integrated luminosity of 35.9 fb−1. The measurement is performed in the decay channel where each Z boson decays to either a pair of electrons or a pair of muons. The fiducial region is defined as: ptLepton > 5 GeV, |etaLepton|< 2.5,pTj1 > 30 GeV, |etaj1| < 4.7, pTj2 > 30 GeV, |etaj2|< 4.7, mjj > 100 GeV.