Carbonate diagenesis is a subject of enormous complexity because of the basic chemical reactivity of carbonate minerals. These carbonate minerals react quickly with natural waters that either dissolve the carbonates, or precipitate new carbonates to bring the water into equilibrium with the host carbonate sediments and rocks. These rock-water interactions either create porosity by dissolution, or destroy porosity by the precipitation of carbonate cements into pore spaces. Carbonate Diagenesis and Porosity examines these important relationships in detail. This volume is published in co-operation with OGCI, and is based on training courses organised by OGCI and taught by Dr. Moore. It is intended to give the working geologist and university graduate student a reasonable overview of carbonate diagenesis and its influence on the evolution of carbonate porosity. It starts with a discussion of the major differences between carbonates and siliciclastics so that the novice will have an appreciation of the basic nature of the carbonate system. Carbonate porosity, its nature and its classification is then discussed so that the relationship between diagenesis and porosity can be established. Environments of diagenesis and their characteristics are outlined, stressing the nature of pore fluids found in each environment. Tools for the recognition of these environments are then discussed with stress on the constraints suffered by each technique. Each major diagenetic environment is then discussed in detail with petrographic, geochemical characteristics outlined, and an in depth discussion of the impact of the environment"s diagenetic processes on porosity development and evolution. Diagenetic models are developed where appropriate and criteria for recognition listed. Case histories illustrating these concepts and models are presented for each major diagenetic environment and sub-environment. Over 160 line drawings illustrate