The invention concerns a method for providing a plurality of receivers with conditional access to broadcast services using a simplified means for managing the control messages required by such conditional access schemes. The method involves providing all information which will allow a registered receiver having the necessary decryption key to access the services without having any prior rights loaded locally. A management center keeps a register of all subscribed receivers, including a list of services to which the receiver is subscribed, and encrypts the services using control words encrypted by the necessary keys. Control messages comprising the control words for decryption are provided within a special channel to which the receiver has permanent access, the special channel being a different one from channels used for broadcasting audio/video services.