AbstractElectronic data interchange (EDI) has heen widely used for the exchange of retail orders and invoices, to avoid the expensive and time-consuming manual entry of data. The extension of this to the aerospace industry is considered here with specific reference to the designing and building of the Eurofighter. With four firms of different nationalities involved in the project, there have been a number of compromises required in the construction of a mutual database. This case shows that standardisation of data formats is not sufficient to enable the exchange of complex design data. Harmonisation of the companies' working practices is also necessary. The costs of such harmonisation, where these working practices are embedded in existing computer systems, can be very high, creating a significant barrier to the use of EDI for technical data exchange.