The introduction of seismic-stratigraphic techniques in the 1970s gave sedimentary geologists in the petroleum industry and academia new tools for predicting lithology and analyzing the depositional history of sedimentary basins. Seismic stratigraphy originally focused on large-scale exploration problems and was based on analyses of 2-D seismic data in areas that were relatively “data-poor” (i.e., few logs, core, or production data). Although these conventional seismicstratigraphic analyses are still used fruitfully, new challenges and opportunities confront the petroleum industry as it faces the need to improve recoveries from mature fields. These areas are commonly data-rich (lots of log, core, and production data), and covered by relatively small 3-D seismic surveys that do not image all of the sequences or systems tracts that include the reservoir rocks. As such, a new mindset is needed, here termed reservoir-scale seismic stratigraphy, to help geoscientists maximize the stratigraphic information they can extract from seismic data. Integration of geological and geophysical concepts and data is critical. Techniques employed by geophysicists for at least the past decade (inversion, seismic attribute studies, seismic facies analysis, etc.) need to become routine parts of the sedimentary geologist’s toolkit, whereas seismic interpreters need to study outcrops, cores, and modern analogs in order to anticipate the presence of depositional features that cannot be resolved seismically. This cross-disciplinary interaction will undoubtedly spawn new breakthroughs in sedimentary geology, reflection seismology, petroleum geology, and related fields (e.g., hydrogeology). These are exciting times.