Primary immunodeficiency disorders (PID) are rare inborn errors of the immune system. Characteristic for PID are the predisposition to recurrent infections, autoimmunity, allergy, and cancer. The identification of the underlying genetic causes and the pathophysiological basis of these rare diseases, are not only important for the development of innovative gene-based therapeutic strategies, but have wide implications for understanding many of the more common immunological disorders. Members of the interdisciplinary PID-NET consortium will work together to define the molecular etiology of inborn disorders of the innate and adaptive immune system. PID-NET will focus on severe combined immunodeficiency disease, autoimmune lymphoproliferative diseases, autoinflammatory diseases and PID with colitis. Furthermore PID-NET scientists will coordinate a national platform to establish innovative cellular model systems to develop and characterize new gene based therapies for patients with defined primary immunodeficiency disorders. A national registry, established during the last years of funding, will be expanded and constitutes a key element of this collaboratory effort. In summary, PID-NET will play a substantial role in coordinating primary immunodeficiency research in Germany and thus will ultimately help to improve diagnosis and therapy of patients with rare inherited immunodeficiency syndromes.