The 10 years development program, succeeded in creating the smartcard contactless technology adapted to the public transportation uses. Some functional choices have been taken into account to answer the transit operators' needs:

- Contactless technology
- Fast, safe transaction (decentralised securityCommunication within the transaction time
- Flexible transport application to build system step-by-step
- Targeted products to address all users and new services
- Upgradable and respect for current standardsMicroprocessor, contact and contactless interface or contactless interface only
- In accordance to ISO 14443, ISO 7816-1, 2, 3, 4 and CEN 1545 Standards

The technology was made accessible to all manufacturers on a fair and non-discriminatory basis, to ensure:
The birth of this technology, suited to the urban public transport needs

- A full products compatibility
- A fair market competitionCalypso is the electronic ticketing standard which defines
- The secured dialogue between cards and terminal

It was developed by a group of European partners from the cities of Brussels in Belgium,
Lisbon in Portugal, Konstanz in Germany, Paris in France and Venice in Italy