Multiboson and VBS measurements in ATLAS and CMS

A review of recent multiboson and vector boson scattering (VBS) measurements from the ATLAS and CMS Collaborations at the LHC is presented. Results are reported from precision diboson cross-section measurements, novel CP-sensitive and polarisation observables in $Wγ$ production, VBS observations in semileptonic and fully leptonic final states including the first measurements at $\sqrt{s}$ = 13.6 TeV, and observations of triboson processes. These results constitute a comprehensive test of the electroweak gauge sector of the Standard Model, and provide stringent constraints on anomalous gauge couplings in the effective field theory framework.