  We identify the exactly solvable theory of the conformal fixed point of (0,2)
Calabi-Yau sigma-models and their Landau-Ginzburg phases. To this end we
consider a number of (0,2) models constructed from a particular (2,2) exactly
solvable theory via the method of simple currents. In order to establish the
relation between exactly solvable (0,2) vacua of the heterotic string, (0,2)
Landau-Ginzburg orbifolds, and (0,2) Calabi-Yau manifolds, we compute the
Yukawa couplings in the exactly solvable model and compare the results with the
product structure of the chiral ring which we extract from the structure of the
massless spectrum of the exact theory. We find complete agreement between the
two up to a finite number of renormalizations. For a particularly simple
example we furthermore derive the generating ideal of the chiral ring from a
(0,2) linear sigma-model which has both a Landau-Ginzburg and a (0,2)
Calabi-Yau phase.
