A system is described for processing voice applications comprising a client device (10) having associated data indicative of its computing capability. The system has access to a plurality of scripts specifying tasks to be performed in a voice-based dialog between a user and the system. The scripts are interpretable at a browser level. A server (20) selects an appropriate script for the client device (10) based on the associated data. An interpreter layer processes the selected script to determine a first set of instructions to be performed on the client device (10) and a second set of instructions to be performed on the server (20) for the dialog. Computation is thus shared between the client device and the server based on the computational capability of the client.