Trends in Nanotechnology (TNT2009) is been launched following the overwhelming success of earlier Nanotechnology Conferences. The TNT2009 edition (September 07-11, 2009) will take place in Barcelona (Spain) in particular to emphasise the importance at the Spanish and European level of the Nanoscience and Nanotechnology activity of the Catalonian region. This high-level scientific meeting series aims to present a broad range of current research in Nanoscience and Nanotechnology as well as related policies (European Commission, etc.) or other kind of initiatives (nanoGUNE, FinNano, GDR-I, etc.). TNT events have demonstrated that they are particularly effective in transmitting information and establishing contacts among workers in this field.