  We show that the S parameter is not finite in theories of electroweak
symmetry breaking in a slice of anti--de Sitter five-dimensional space, with
the light fermions localized in the ultraviolet. We compute the one-loop
contributions to S from the Higgs sector and show that they are logarithmically
dependent on the cutoff of the theory. We discuss the renormalization of S, as
well as the implications for bounds from electroweak precision measurements on
these models. We argue that, although in principle the choice of
renormalization condition could eliminate the S parameter constraint, a more
consistent condition would still result in a large and positive S. On the other
hand, we show that the dependence on the Higgs mass in S can be entirely
eliminated by the renormalization procedure, making it impossible in these
theories to extract a Higgs mass bound from electroweak precision constraints.
