Inclusion Criteria:  • Consenting people with cystic fibrosis of any age, genotype, transplant status and disease severity  Exclusion Criteria:  Refusal to give informed consent Contraindication to venepuncture.  Participants already enrolled in a clinical trial are eligible for enrollment in this study. Inclusion in CAR-CF should not preclude enrollment in other observational clinical trial studies or clinical trials of an investigational medicinal product (CTIMP).