The CURP Clave Única de Registro de Población program is used to manage access to government services in Mexico. A valid CURP is needed to get a driver's license, register a vehicle, apply for employment, file taxes, start a business, open a bank account, use government healthcare services, obtain government-sponsored senior discounts, and for many other matters. When the program began the CURP document was a wallet-sized card. The format has now changed and today the CURP document is a letter-sized certificate, not a card.