The 15th Biennial Meeting of the European Society of Immunodeficiencies (ESID 2012), organised together with the International Nursing Group for Immunodeficiencies (INGID) and the International Patient Organisation for Primary Immunodeficiencies (IPOPI), will be held in the beautiful city of Florence, Italy. ESID 2012 offers an advanced scientific programme with a leading international faculty, new approaches to diagnosis and treatments, interactive discussions, opportunities for collaborative research, and networking events.