he International Workshop "New sources, novel phases, new applications", the third of the series on "Oxide based materials", was held September 13 to 16, 2004 at Societá del Casino Sociale in Como, Italy. The workshop brought together experimental and theoretical scientists of different origins and expertise to exchange information on common scientific research fields, especially on all those materials whose features and properties depend on the interaction between surface and ionic and/or molecular species. Knowledge of familiar materials was compared and experiences shared on a varied range of different materials, often new materials, including metal oxides, zeolites and other microporous compounds, mesoporous silicates and silica, hybrid inorganic-organic compounds, soil aggregates, layered materials, and bioactive glasses.