The Prionopidae are a family uniting some smallish to mid-sized songbird species. One group, the helmetshrikes, were included with the true shrikes in the family Laniidae, later on split between several presumably closely related groups such as bushshrikes (Malaconotidae) and cuckooshrikes (Campephagidae), but are now considered sufficiently distinctive to be separated from that group as the family Prionopidae. The Prionopidae and the two former are part of a group which is generally rather homogenous but also includes the diverse vangas. The Campephagidae are a bit more distinct. (source)