Chronic GvHD (cGvHD) is a multi-organ allo and auto immune disorder and a major cause of non-relapse morbidity and mortality following allogeneic haematopoietic stem cell transplantation. It occurs in an estimated 50% of patients per year worldwide and causes a plethora of co-morbidities. There is a lack of coordination at the European research level into cGVHD diagnosis and therapy and this impacts on patient care, due to a non-uniform treatment approach across transplant centres. This COST Action will serve as a platform for industry, clinical teams and researchers from numerous disciplines, including bioinformatics, immunology, epidemiology, genetics and cell biology, to enable the dissemination of integrated clinical and laboratory information via established and improved databases. The COST Action will promote novel research as well as more uniform treatment of the disease. Innovation will be accelerated by coordination, networking and introduction of new technologies and therapies for the benefit of patients by being able to more accurately predict and treat the disease and its co-morbidities. Early career investigators (ECI’s) will learn how genomics, proteomics and immunology interact to provide a more personalised medicine approach to treat disease and improve patient outcomes. By studying large-scale populations and coming together as a network, we will further understand the pathogenesis of cGvHD, its subsets and associated co-morbidities and develop a coordinated approach to therapy. Workshops on innovative multidisciplinary research will include, genetics, epigenetics (DNA methylation, microRNAs free and in exosomes) proteomics, lipidomics, the role of the microbiome, and novel stem cell therapies.