Embodiments may provide techniques to screen for, detect, and prevent connection of robocalls. For example, in an embodiment, a method, implemented in a computer system comprising a processor, memory accessible by the processor, and computer program instructions stored in the memory and executable by the processor, may comprise receiving, at a telecommunications switch, a request to initiate a call from an originating party, selecting, at the telecommunications switch, from a list of terminating carrier networks, a media server, routing, at the telecommunications switch, the request to initiate the call to the media server, forwarding, from the media server, a media prompt requesting the originating party to enter a response to the media prompt, and when the originating party does not enter a correct response to the media prompt, forwarding, from the media server, an indication that the call is forbidden.