Figure 1 summarizes estimates for the time-scales over which fossil assemblages accumulate, based on the findings summarized by the various authors of this volume, and organized according to major taxonomic groups in terrestrial and marine environments. For each group, actualistic estimates are based primarily on field evidence for the durability of organic remains, either from time-lapse tracking of carcasses or from direct-dating of individuals in Recent death assemblages; other methods include extrapolating from known rates of sediment accumulation and rates and depths of mixing. Estimates from the fossil record are based almost exclusively on indirect evidence, such as bracketing of assemblages by biostratigraphic and other chronostratigraphic datums, and actualistic rates of formation for the kinds of beds and facies that contain assemblages. The reader should see individual chapters for details and original sources of data.