What functionality to include in an electronic spare parts catalog should depend on the requirements of the user. The available functionality and  the timeliness of the data are decisive factors for the users' acceptance of electronic catalogs.

The core functionality needed is the fast and easy navigation between single catalog pages and illustrations and parts lists. A click on an object in an illustration should result in the display of the respective parts lists information. A click on a parts lists entry should highlight the relevant graphical object.

There should also be the possibility of collecting single items in a "shopping basket" that can be used for placing an order. This order could then be printed, faxed or sent electronically.