Predicting and characterizing the subsurface remains a key endeavor for applied geoscientists. Biostratigraphy provides critical support through its ability to support correlation within the subsurface and to determine depositional environments of sedimentary rock units. A combination of time-based correlation and paleoenvironmental interpretation under the umbrella of sequence stratigraphy helps organize stratigraphic information and allows for predictions to be made as to the sedimentary successions and their character that can be expected between data-points and in data-poor regions. Issues that can be typically resolved by biostratigraphy occur at a wide variety of scales and – in decreasing order of scale – include generation of play concepts and global- and basin-scale play screening through support of correlation, Earth systems science context (e.g. paleoclimate, eustasy), gross depositional environment mapping, and sequence stratigraphy; age frameworks for basin modelling; appraising assets; and the effective, efficient and safe exploitation of assets through operational biostratigraphy including casing/coring picks and biosteering. Applied biostratigraphy has supported the ongoing efforts of the oil and gas industry for over one hundred years and the lessons from these endeavors can be applied to alternative subsurface use cases, including storage, defining optimal locations for low-carbon energy sources such as geothermal, and for engineering projects associated with, for example, wind-farm location. Importantly, biostratigraphic data is suitable for assisted interpretation arising from the digital revolution, meaning that data gathering and interpretation are becoming faster and better integrated.