  String theory, if it describes nature, is probably strongly coupled. In light
of recent developments in string duality, this means that the ``real world''
should correspond to a region of the classical moduli space which admits no
weak coupling description. We exhibit, in the heterotic string, one such region
of the moduli space, in which the coupling, $\lambda$, is large and the
``compactification radius'' scales as $\lambda^{1/3}$. We discuss some of the
issues raised by the conjecture that the true vacuum lies in such a region.
These include the question of coupling constant unification, and more generally
the problem of what quantities one might hope to calculate and compare with
experiment in such a picture.
