  We show that a particular class of effective low energy supergravity theories
motivated by string theory can provide a promising framework for models of
hybrid inflation in which the potential energy which drives inflation
originates from the F-term of the effective supergravity theory. In the class
of models considered the inflaton is protected from receiving mass during
inflation by a generalisation of the Heisenberg symmetry present in no-scale
supergravity models. The potential during inflation takes the positive definite
form $V\sim |F_S|^2 + |F_T|^2 -3$, which allows the possibility that $V\ll
m_{3/2}^2 M_P^2$ through the cancellation of the positive dilaton and moduli
contribution against the negative term. We discuss a toy example where this is
realised, then describe the application of this result to realistic models
focusing on a particular example in which the $\mu$ problem and the strong
CP-problem are addressed.
