The present experimental and theoretical knowledge of the physics of
electroweak symmetry breaking is reviewed. Data still favor a light Higgs
boson, of a kind that can be comfortably accommodated in the Standard Model or
in its Minimal Supersymmetric extension, but exhibit a non-trivial structure
that leaves some open questions. The available experimental information may
still be reconciled with the absence of a light Higgs boson, but the price to
pay looks excessive. Recent theoretical ideas, linking the weak scale with the
size of possible extra spatial dimensions, are briefly mentioned. It is
stressed once more that experiments at high-energy colliders, such as the
Tevatron and the LHC, are the crucial tool for eventually solving the Higgs
puzzle.Comment: 18 pages, 13 figures, invited talk at the 20th International
Symposium on Lepton and Photon Interactions at High Energies (Lepton Photon
01), Rome, Italy, 23-28 July 200