A multi-tier application for interaction with a user interface comprises a presentation tier (e.g. a web server with a JSP/servlet engine) and a business logic tier (e.g. an application server) to manipulate data for subsequent presentation on the user interface. A direction module, such as a requested resource definition, has a plurality presentation and function definitions for accessing a presentation component defined externally to the requested resource definition and the function definition for identifying a function component also defined externally to the requested resource definition. The direction module can have a plurality of coupled directions, including a function direction to direct a corresponding functional component to perform a data processing function and provide a data processing output, and a presentation direction to direct a corresponding presentation component to incorporate the data processing output, when applicable, into a presentation template to produce a presentation element for the user interface.