Topics: SM Higgs boson: theory and experiment Extensions of the minimal scalar sector of the Standard Model, e.g. multi Higgs-dublet models, doublet-singlet models, the Georgi-Machacek model, ... Experimental constraints on possible scalar sectors Effective field theory in Higgs physics Scalars in cosmology: dark matter, baryogenesis, phase transitions, inflatons, axions, relaxions, etc. Scale-invariant scalar sectors Composite Higgs bosons Elementary scalars within extra dimensions: gauge-Higgs unification, stabilization of extra dimensions, radions, bulk scalars, etc... Fundamental scalars within supersymmetric extensions of the SM Future experimental searches for scalars, e.g. at LHC, FCC or ILC