Dry eye syndrome (DES) is characterized by an inadequate volume and/or quality of tears resulting in chronic ocular surface irritation and inflammation. Affecting up to 30 % of adults, DES has a considerable impact on visual function and quality of life. DES may complicate allergic ocular disease and allergy medication may exacerbate DES. The pathophysiology of DES involves osmotic, mechanical and inflammatory insults to the tear film, epithelium and subepithelial nerve plexus. Various immune-related molecular targets have been the focus of research aimed at developing new therapeutic agents for treating DES. This article provides an overview of established, new and future agents for treating DES.