Abstract: A designer builds a condensed, generic form of a spreadsheet which is a definition file. This can be designed in Microsoft Excel, following a set of guidelines, or using a high level symbolic language. If required, HTML files, can be produced directly from the Excel definition file to enable the user to, input parameters using a web browser. A user defines the various parameters that are to be used for their particular spreadsheet and the software of the present invention expands the template's rows and columns according to those requirements, working out the effect on the formulae and linked cells as this takes place. Behind the scenes a set of information tables are built, either in memory or in a file, based on the information in the definition file. These tables are processed in a structured way to build the spreadsheet formulae, reference other tables and build any objects required to operate the model. Formulae are copied and/or rebuilt depending on the circumstances in which they will be used.