The microbiome in allergic disease: Current understanding and future opportunities—2017 PRACTALL document of the American Academy of Allergy, Asthma & Immunology and the European Academy of Allergy and Clinical Immunology https://doi.org/10.1016/j.jaci.2017.02.007 Abstract: PRACTALL is a joint initiative of the American Academy of Allergy, Asthma & Immunology and the European Academy of Allergy and Clinical Immunology to provide shared evidence-based recommendations on cutting-edge topics in the field of allergy and immunology. PRACTALL 2017 is focused on what has been established regarding the role of the microbiome in patients with asthma, atopic dermatitis, and food allergy. This is complemented by outlining important knowledge gaps regarding its role in allergic disease and delineating strategies necessary to fill these gaps. In addition, a review of progress in approaches used to manipulate the microbiome will be addressed, identifying what has and has not worked to serve as a baseline for future directions to intervene in allergic disease development, progression, or both. First Author: Yvonne J.Huang Correspondence: Thomas A.Fleisher All Authors: YvonneJ.HuangMDaBenjaminJ.MarslandPhDbSupindaBunyavanichMD,MPH,MPhilcLiamO'MahonyPhDdDonald Y.M.LeungMD, PhDeAntonellaMuraroMD, PhDfMDg Joseph HernandezMD, PhD ?Scott D.BoydMD, PhD Stephen J.Galli MD