The international conference Undiagnosed Day 2026 – Where Diagnosis Becomes Hope: The Power of Collaboration and Technology in Rare Diseases, dedicated to contemporary diagnostic challenges in rare and undiagnosed diseases, was held on 30th April 2026 at the Invasive Medicine Centre of the University Clinical Centre, the MUG hospital. The event brought together experts from Poland and abroad, representing the scientific and clinical communities, public and system-level institutions, as well as patient organisations. – The strength of the Medical University of Gdańsk lies not only in its