The higher-level classification of the insect order Diptera is in a constant state of flux, and over the last several decades, a vast number of names have been variously proposed, rejected, had their definitions changed, or altered spelling. Keeping track of all of these names is a challenging task, especially as there is no consensus as to the proper classification that should be used for this order, as well as reflecting a more fundamental challenge to the entire underlying principles of classification, which is especially evident among Dipteran systematists. The purpose of this article is to serve as a reference in situations where a reader may encounter an obsolete name in a printed or online resource, and otherwise be unable to find it.