ABSTRACT: The Midcontinent Basin of North America contains well-exposed Pennsylvanian lithostratigraphic units and largely well-defined biostratigraphic zones that form the basis for the North American regional stages. These are the Morrowan, Atokan, Desmoinesian, Missourian, and Virgilian, in ascending order, of which only the Atokan-Desmoinesian stage boundary is not yet well defined. The Morrowan-Atokan part of the succession is exposed mainly in northwestern Arkansas and eastern Oklahoma. The Desmoinesian-Virgilian part of the succession on the northern Midcontinent Shelf (Iowa and Nebraska through Missouri and Kansas to northern Oklahoma) is best exposed south of the limit of Pleistocene glaciation from Kansas City southward, where well over 200 lithostratigraphic formations and members, and at least 120 genetic cyclothems of various scales are recognized. Biostratigraphic zones based primarily on conodonts, plus stratigraphic position, allow correlation of most major cyclothems into the Illinois Basin and several of them into the Appalachian Basin as well.