A method for performing a conditional content in a terminal, the method comprising - delivering a software product to the terminal, the software product comprising a function for generating an authentication request required for ordering at least one part of the conditional content, and a function for performing the at least one part of the conditional content, - transmitting the conditional content over a data transmission network, to the terminal, - generating an authentication request identifying the at least one part of the conditional content at least partly by means of said function included in the software product for delivery at least partly to an authentication server for generating an authentication code corresponding to said authentication request, - generating an authentication code for delivery to said terminal using the authentication server and based at least partly on said authentication request delivered to the authentication server, - delivering said authentication code to said terminal, and - performing said at least one part of the conditional content by activating the function of the software product for performing the conditional content with the aid of said authentication code, characterised in that the data transmission network is a digital television transmission network, the software is delivered over the digital transmission network to the terminal, the authentication request and the authentication code are delivered over a different network than the software and the conditional content, and the authentication request and the authentication code are sent over a mobile phone connection, a payment of the conditional content ordered in the authentication request is checked by the authentication server before the authentication code is sent by sending an enquiry to an operator of the mobile connection, which delivers the authentication request and carries out invoicing, the delivered authentication code is fed to terminal using a keyboard or a remote control of the terminal, and the conditional content is displayed by a digital television that is connected to the terminal. - delivering a software product to the terminal, the software product comprising a function for generating an authentication request required for ordering at least one part of the conditional content, and a function for performing the at least one part of the conditional content, - transmitting the conditional content over a data transmission network, to the terminal, - generating an authentication request identifying the at least one part of the conditional content at least partly by means of said function included in the software product for delivery at least partly to an authentication server for generating an authentication code corresponding to said authentication request, - generating an authentication code for delivery to said terminal using the authentication server and based at least partly on said authentication request delivered to the authentication server, - delivering said authentication code to said terminal, and - performing said at least one part of the conditional content by activating the function of the software product for performing the conditional content with the aid of said authentication code,