A method for stochastically modelling bidirectionality in chart parsing is presented. A bidirectional parser, which starts analysis from certain dynamically determined positions of the sentence (the islands), has been built. This island-driven parser uses the stochastic model to guide the recognition process. The system has been trained and tested over two wide-coverage corpus: Spanish Lexesp and English Penn Treebank. Results regarding comparison of our approach with the basic Bottom-Up are encouraging.