It's an Arg1 extravaganza as Reena Sharma, Sara Olofsson, Karolina Stepien and Alison Woodall discuss three separate papers looking at the Salford Royal experience of a cohort of adults with Arginase 1 deficiency and the wider health and societal cost of the condition. Retrospective analysis of arginase 1 deficiency progression in adults over 5 years at a single metabolic centre Reena Sharma et al https://doi.org/10.1002/jmd2.12450 Disease burden among patients with Arginase 1 deficiency and their caregivers: A multinational, cross-sectional survey Sara Olofsson et al https://doi.org/10.1002/jmd2.12456 Societal costs and quality of life associated with arginase 1 deficiency in a European setting – a multinational, cross-sectional survey Sara Olofsson et al https://doi.org/10.1080/13696998.2024.2400856