Introduction. Part I: Submarine hot springs and venting environments -- cradle of life. 1. Energy, entrophy and the onset of hydrothermal convection, relevance to beginning of life. 2. Organic synthesis in seafloor hydrothermal environments. 3. A genomic approach to early microbial evolution and environments. 4. Earliest seafloor hydrothermal systems on Earth; comparison with modern analogues. Part II: Geological and geochemical processes responsible for organic matter (OM) accumulation and preservation. 1. Earliest sedimentary systems on Earth. 2. Modes of accumulation of carbonaceous matter in the Barberton Greenstone Belt, South Africa. 3. Archaean hydrothermal systems in the Barberton Greenstone Belt, South Africa. 4. Microbially induced sedimentary structures in Archaean silicastic rocks. 5. Microbial alteration features in Archaean seafloor lavas. 6. Tectonic controls on Archaean atmospheric, oceanic and biological evolution. Part III: Evidence and record of earliest life on Earth. 1. Integration of observational and geochemical analytical methodologies to identify Archaean microbial remains. 2. Fluid inclusion microanalysis for detection of biosignatures in the Archaean. 3. Palaentological and paleoenvironmental studies of early Archaean stromatolites. 4. Evidence for early Archaean oxygenic photosynthesis from Greenland. 5. Geochemical isotopic methods in support of early Archaean microbial remains. Part IV: Specialised geochemical and physical techniques used to resolve the nature and origin of Archaean OM. 1. Carbon isotopes. 2. Nitrogen isotopes. 3. Non-traditional stable isotopes. 4. Elemental ratios. 5. NanoSIMS analysis; submicron scale elemental and isotopic composition. 6. Transmission electron microscopy. 7. Nuclear Magnetic Resonance. 8. Detection of molecular fossils of biological lipids (biomarkers). Part V: Biogenic versus abiogenic carbonaceous matter production under hydrothermal conditions, implication to earliest life. 1. Abiotic synthesis of organic compounds in sulphur-rich hydrothermal systems. 2. Formation of lipids by Fischer-Tropsch-type synthesis under simulated hydrothermal conditions. 3. Experimental models of prebiotic processes suggested as precursors to earliest microbial life forms. 4. Observational and geochemical evidence for an abiotic origin for carbonaceous compounds in Archaean seafloor hydrothermal dykes. Summary, discussion and future research.