ABSTRACT: Harry Eugene Wheeler (1907-1987) of the University of Washington was a pioneer of genetic stratigraphic principles that form the basis of our modern concept of sequence stratigraphy. Wheeler’s papers on what he liked to refer to as “stratology†included the classification of stratigraphic units into lithostratigraphic and biostratigraphic entities, as well as cyclothems, unconformity-bounded units, and the analysis of base-level and its role in forming stratigraphic discontinuities. His work on unconformity-bounded “sequences†ultimately led the International Subcommission on Stratigraphic Classification to define them formally in 1987. The plots used to clarify the time-relationships of rock units are now referred to as “Wheeler diagramsâ€. It is not uncommon that, in any scientific paradigm shift, many of the key pioneers are not fully recognized for their contributions at the time, being significantly ahead of prevailing concepts. It is also not uncommon that, by the time their points of view come into vogue, their contributions may have been largely forgotten with greater recognition given to those who synthesized or “popularized†their concepts. This is certainly true in the fields of seismic and sequence stratigraphy, where, despite the theoretical framework for sequence analysis formulated by Wheeler (1958a), little reference was made to Wheeler’s work in the early formulation of these concepts in the 1970s and 1980s. Wheeler, schooled by Blackwelder, Mueller, and Schenck at Stanford and armed with the base-level concept of Joseph Barrell, was one of the first to recognize the concept of time stratigraphy. Due to his unorthodox view of stratigraphy, Wheeler was involved in one controversy after another and his views were deemed to be provocative. While the valuable contributions of latter practitioners and synthesizers are justifiably lauded, the works of original pioneers such as Harry Eugene Wheeler are largely underappreciated.