Abstract: A method and system for providing cross-carrier contact information for mobile users of mobile communication devices and other mobile communication devices provides a single registry of user profiles, wherein each user profile is established and maintained by a user so that each user may control how and by whom they are contacted. The registry of user profiles may be accessed with a client software application on a calling party's mobile communication device. The calling party may transmit a look-up request to the registry over a data channel. The registry receives the look-up request and locates a user profile that matches the look-up request and provides the user profile to the calling mobile communication device. The user profile does not display the mobile communication device number for the called mobile communication device.