Four Dimensional Supergravities from Five Dimensional Brane Worlds

We give the explicit form of the four dimensional effective supergravity action which describes low energy physics of the Randall-Sundrum model with moduli fields in the bulk and charged chiral matter living on the branes. The relation between 5d and 4d physics is explicit - the low energy action is derived from the compactification of a locally supersymmetric model in five dimension. The presence of odd $Z_2$ parity scalars in the bulk gives rise to effective potential for the radion in four dimensions. We describe the mechanism of supersymmetry breaking mediation which relies on non-trivial configuration of these $Z_2$ odd bulk fields. Broken supersymmetry leads to stabilization of the interbrane distance.