1 Introduction: The importance of sedimentary organic matter.- 2 The nature of organic matter in sediments.- 3 Production and delivery flux of planktonic organic matter.- 4 Biological degradation and consumption of organic matter.- 5 Abundance of organic matter in sediments: TOC, hydrodynamic equivalence, dilution and flux effects.- 6 Organic matter preservation: the effects of oxygen deficiency.- 7 Origin and nature of the Phytoclast Group.- 8 Origin and nature of the Amorphous Group.- 9 Origin and nature of the Palynomorph Group, Phytoplankton Subgroup.- 10 Origin and nature of the Zoomorph Subgroup, and the origin, nature and distribution of the Zooclast Group.- 11 Distribution of the Phytoclast Group.- 12 Distribution of the Amorphous Group.- 13 Distribution of the Palynomorph Group: Sporomorph Subgroup.- 14 Distribution of the Palynomorph Group: Phytoplankton Subgroup, marine dinoflagellate cysts (dinocysts).- 15 Distribution of the Palynomorph Group: Phytoplankton Subgroup, marine prasinophyte phycomata.- 16 Distribution of the Palynomorph Group: Phytoplankton Subgroup, chlorococcale algae.- 17 Distribution of the Palynomorph Group: Phytoplankton Subgroup, Acritarcha.- 18 Distribution of the Palynomorph Group: Phytoplankton Subgroup, cyanobacteria and Rhodophyta.- 19 Distribution of the Palynomorph Group: Zoomorph Subgroup.- 20 Palynological kerogen classification.- 21 Bulk geochemical characterization and classification of organic matter: elemental analysis and pyrolysis.- 22 Bulk geochemical characterization and classification of organic matter: carbon:nitrogen ratios and lignin-derived phenols.- 23 Bulk geochemical characterization and classification of organic matter: stable carbon isotopes (?13C).- 24 Palynofacies in a sequence stratigraphic context.- 25Some practical aspects of palynofacies analysis.- Appendix A Density of particulate organic matter and kerogen and some associated materials.- Appendix C Carbon:nitrogen weight ratios of organic matter and some Recent and ancient sediments.- Appendix D Prasinophyte occurrences in dysoxic-anoxic facies of Silurian to Quaternary age (in stratigraphic order).