Formal Chronostratigraphic Units are defined in the International Stratigraphic Guide on the basis of boundary stratotypes and then extended globally as isochronous units. They are unrealistic for application to late-Quaternary history, which involves events that are demonstrably time-transgressive owing to measurable lags between the causative force and the geologic response. Natural geologic time units that are diachronous globally are preferred because they represent events identifiable in the stratigraphic record. A similar objection is raised against formal Chronostratigraphy for the pre-Quaternary: recognizable biostratigraphic or lithostratigraphic units on which the geologic time scale has been built are diachronous globally, for they depend on slow evolutionary or tectonic processes. The imposition of Chronostratigraphic Units that are unrecognizable stratigraphically at a distance away from the type locality introduces an unnecessary terminology in the efforts of stratigraphers to econstruct the geologic history.