Volcanic degassing: introduction, C Oppenheimer, D M Pyle and J Barclay • Dynamics of magma degassing, R S J Sparks • Experimental constraints on volatile abundances in arc magmas and their implications for degassing processes, B Scaillet and M Pichavant • Water diffusion in natural potassic melts, C Freda, D R Baker, C Romano and P Scarlato • H20 and halogens in volcanic clasts: traxcers of degassing processes during plinian and dome-building eruptions. B Villemant, G Boudon, S Nougrigat, S Poteaux and A Michel • A model for the saturation of C-O-H-S fluids in silicate melts, R Moretti, P Papale and G Ottonello • Sulphur release from flood lava eruptions in the Veidivotn, Grimsvotn and Katla volcanic systems, Iceland, T Thordarson, S Self, D J Miller, G Larsen and E G Vilmundardottir • Particles from the plume of Popocatepetl Volcano, Mexico - the FESEM/EDS Approach, J H Obenholzner, H Schroettner, P Golob and H Delgado • Optical sensing of volcanic gas and aerosol emissions, A J S McGonigle and C Oppenheimer • Altitude effects on COSPEC measurements of volcanic SO2 emission rates, T M Gerlach • Volcanic eruption detection bythe Total Ozone Mapping Spectrometer (TOMS) instruments: a 22-year record of sulphur dioxide and ash emissions, S A Carn, A J Krueger, G J S Bluth, S J Schaefer, N A Krotkov, I M Watson and S Datta • Rainwater and ash leachate analysis as proxies for plume chemistry at Soufriere Hills Volcano, Montserrat, M Edmonds, C Oppenheimer, D M Pyle and R A Herd • Magma extrusion dynamics revealed by high-frequency gas monitoring at Soufriere Hills Volcano, Monsterrat, S R Young and B Voight • CO2 Emissions from Fumarolic Ice Towers, Mt. Erebus Volcano, Antartica, L J Wardell, P R Kyle and A R Campbell • Fumarole migration and fluid geochemistry at Poas Volcano (Costa Rica) from 1998 to 2001, O Vaselli, F Tassi, A Minissale, G Montegrossi, E Duarte, E Fernandez, E Fernandez-Fernandez and F Bergamaschi • Degassing processes of Popocatepetl and Volcan de Colima, N R Varley and Y Taran • FTIR remote sensing of Fractional Magma Degassing at Mt. Etna, Sicily, M Burton, P Allard, F Mure and C Oppenheimer • The Tropospheric Sulphur cycle and the role of Volcanic SO2, D S Stevenson, C E Johnsons, C E Johnson, W J Collins and R G Derwent • The 12,900 yr BP Lacher eruption: estimation of volatile yields and simulation of their fate in the plume, C Textor and H F Graf • Changes in stratospheric composition, chemistry, radiation and climate caused by volcanic eruptions, R G Grainger and E J Highwood • Compositional variation in topospheric volcanic gas plumes: evidence from ground-based remote sensing, L A Horrocks, C Oppenheimer, M R Burton and H J Duffell • Correlations between eruption magnitude, SO2 yield, and surface cooling, S Blake • Environmental impacts of tropospheric volcanic gas plumes, P Delmelle • Illness and elevated human mortality inEurope coincident with the Laki Fissure eruption, J Grattan, M Durand and S Taylor