Using the linear multiplet formulation for the dilaton superfield, we
construct an effective Lagrangian for hidden sector gaugino condensati
on in string effective field theories with arbitrary gauge groups and
matter. Non-perturbative string corrections to the Kahler potential ar
e invoked to stabilize the dilaton at a supersymmetry breaking minimum
of the potential. When the cosmological constant is tuned to zero the
moduli are stabilized at their self-dual points, and the vevs of thei
r F-component superpartners vanish. Numerical analyses of one- and two
-condensate examples with massless chiral matter show considerable enh
ancement of the gauge hierarchy with respect to the E-8 case. The non-
perturbative string effects required for dilaton stabilization may hav
e implications for gauge coupling unification. As a comparison, we als
o consider a parallel approach based on the commonly used chiral formu
lation. (C) 1997 Elsevier Science B.V.