To familiarize the reader with the milestones of the DEFASE (Definition of Food Allergy Severity) project. This World Allergy Organization (WAO) initiative has recently developed the first international consensus-based classification system of severity associated with IgE-mediated food allergy as a whole disease incorporating multidisciplinary perspectives from different stakeholders involved.

After a systematic review of current evidence on the definition of severity of food allergy, an e-Delphi methodology has been applied to obtain the consensus/agreement through repeated rounds of survey. This comprehensive scoring system has been developed to be used in research settings in its current version with the scope of stratifying the severity of a clinical situation of food allergy.

Notwithstanding the limitations due to the complexity of the matter, the recent developed DEFASE definition will be relevant for establishing the levels of diagnostic, management and therapeutic commitment for the disease in the various geographical contexts. Future research should focus on internal and external validation of the scoring system, tailoring of these models to different food allergenic sources, populations, and settings.