  A new physical origin for electroweak symmetry breaking is proposed,
involving compact spatial dimensions of scale 1/R \approx 1 TeV. The higher
dimensional theory is supersymmetric, and hence requires the top-quark Yukawa
coupling to be localized on some ``Yukawa brane'' in the bulk. The short
distance divergence in the Higgs-boson mass is regulated because supersymmetry
is unbroken in the vicinity of this Yukawa brane. A finite, negative Higgs
mass-squared is generated radiatively by the top-quark supermultiplet
propagating a distance of order R from the Yukawa brane to probe supersymmetry
breaking. The physics of electroweak symmetry breaking is therefore closely
related to this top propagation across the bulk, and is dominated by the mass
scale 1/R, with exponential insensitivity to higher energy scales. The masses
of the superpartners and the Kaluza-Klein resonances are also set by the mass
scale 1/R, which is naturally larger than the W boson mass by a loop factor.
  Explicit models are constructed which are highly constrained and predictive.
The finite radiative correction to the Higgs mass is computed, and the Higgs
sector briefly explored. The superpartner and Kaluza-Klein resonance spectra
are calculated, and the problem of flavor violation from squark and slepton
exchange is solved. Important collider signatures include highly ionizing
charged tracks from stable top squarks, and events with two Higgs bosons and
missing transverse energy.
