Asthma and allergic diseases (food allergies, rhinitis, eczema) are the most common chronic diseases in childhood and adolescence. They usually start before school-age and are responsible for a heavy burden of ill health, including premature death. In response, we propose an innovative scientific research program which embraces a truly trans-disciplinary team science approach, and is of fundamental relevance both to biomedical research and to evidence-based health science more broadly. UNICORN builds directly on the substantive prior investments in both the science and infrastructure underpinning research in this domain. The project will assist UK to leverage its cohort studies with a focus on asthma and allergy more productively, and to develop a sustainable, scalable scientific infrastructure to facilitate future work in this and other biomedical domains.