A modus operandi for Precambrian stratigraphy is suggested which combines the geochronometrical scale and late Proterozoic chronostratigraphy. The development of Phanerozoic stratigraphical classification is followed from the pioneering days of Murchison, through the growing understanding of fossils in relation to time and the later distinction of rock and time-rock, to the advent of the golden spike. Criticisms of chronostratigraphy (global standard stratigraphy) are assessed and its value upheld. Stratigraphical procedures such as those of event stratigraphy are useful in particular situations, but correlative methods in the Phanerozoic are dominated by biostratigraphy. Examples are taken of its use and potential in North American Cordilleran Palaeozoic stratigraphy, in the Triassic System as a whole, and in the Caledonides of Britain and Ireland.