Over the last few years, three specific eosinophil activating peptides, eotaxin-1, -2 and -3, members of the chemokine family have been identified. These cytokines exert a number of functions on eosinophils including chemotaxis, transendothelial migration and induction of the release of reactive oxygen species. Eosinophils are considered to play an important role in allergic disease by causing tissue damage through the release of toxic proteases, lipid mediators, cytokines and oxygen free radicals. This article reviews the role of eotaxins in asthma and nasal polyps. Discussion focuses on therapeutic guidelines, particularly as it has been shown that CCR3, the major chemokine receptor in eosinophils, serves as a eotaxin receptor.