This paper details the fraudulent robocalling problem, focusing on CLI Spoofing, which enables the majority of these calls to reach their intended victims. The FCC-mandated STIR/SHAKEN solution is described and then a typical call is followed in detail as it makes away across the network, encountering STIR/SHAKEN processing as it goes. The complexity associated with service provider implementations of STIR/SHAKEN is drawn out and this paper concludes by prescribing the tonic for that complexity, NetNumber’s Guaranteed Caller™ family of STIR/SHAKEN solutions, a family designed from the ground up with the overriding objective of simplifying the service provider journey to STIR/SHAKEN compliance.