  We consider the problem of supersymmetry and electroweak breaking in a 5d
theory compactified on an $S^{1}/Z_{2}$ orbifold, where the extra dimension may
be large or small. We consider the case of a supersymmetry breaking 4d brane
located at one of the orbifold fixed points with the Standard Model gauge
sector, third family and Higgs fields in the 5d bulk, and the first two
families on a parallel 4d matter brane located at the other fixed point. We
compute the Kaluza-Klein mass spectrum in this theory using a matrix technique
which allows us to interpolate between large and small extra dimensions. We
also consider the problem of electroweak symmetry breaking in this theory and
localize the Yukawa couplings on the 4d matter brane spatially separated from
the brane where supersymmetry is broken. We calculate the 1-loop effective
potential using a zeta-function regularization technique, and find that the
dominant top and stop contributions are separately finite. Using this result we
find consistent electroweak symmetry breaking for a compactification scale {$
1/R \approx 830$ GeV} and a lightest Higgs boson mass $m_{h} \approx 170$ GeV.
