The Pliocene, specifically the late Pliocene, has been a focus of paleoclimate research formore than 25 years. Synoptic regional and global reconstructions along with high-resolution time-series have produced nuanced conceptual models of paleoenvironmental conditions and enhanced our understanding of climate variability and climate sensitivity from the Late Pliocene, the most recent interval of global warmth similar to what is projected for the end of the 21st century. These data are used as a source of boundary conditions for climate models as well as ameans of verification of global climate model experiments. In this note, we introduce a measure of stratigraphic fidelity, ß, used to characterize the chronology and achievable resolution of an ever-growing library of Pliocene paleoenvironmental time-series. The ß index serves as an aid to end-users by allowing selection of time-series that meet the stratigraphic requirements of a particular study.