Abstract: An architecture is provided for user applications in a computer system including a core application executable by the system and having a data entry space. A field overlay executable by the system, although not necessarily independently executable, stacks functions on top of the core application and imposes a structure on the data entry space to become an extension of the core application, thus creating additional user applications driven by task needs. If implemented in an object-oriented manner, the field overlay inherits attributes of the core application. Links and macros within the field overlays may improve the effectiveness of the core application in accomplishing the desired task.