Introduction.- Volcano-hydrologic Hazards from Volcanic Lakes.- The Chemical Composition and Evolution of Volcanic Lakes.- Gases in Volcanic Lake Environments.- Isotope Fractionation and HCl Partitioning During Evaporative Degassing from Active Crater Lakes.- Molten Sulfur Lakes of Intraoceanic arc Volcanoes.- Crater Lake Energy and Mass Balance.- CO 2 Degassing from Volcanic Lakes.- The Comparative Limnology of Lakes Nyos and Monoun, Cameroon.- Modelling Air Dispersion of CO 2 from Limnic Eruptions.- Microbial Life in Volcanic Lakes.