Conventional non-adjuvanted influenza vaccines have shown suboptimal immunogenicity in subjects at high risk for complications, such as the elderly. Between the several strategies proposed to develop more immunogenic vaccines than the conventional ones, a promising option is represented by the administration of non-adjuvanted vaccine through the intradermal (ID) route. This paper summarizes and discusses the main results recently obtained in clinical trials investigating the safety, tolerability and immunogenicity of new ID influenza vaccines, containing standard or reduced antigen dosages, in different age-groups.