Coeliac disease is an autoimmune disorder of the small intestine which occurs in genetically predisposed individuals. CD is caused by an inflammatory T-cell response to the protein gluten and the treatment is a lifelong gluten-free diet. CD may be identified by non-invasive tests which measure the specific coeliac antibodies and HLA-DQ2/DQ8 genotypes, and by an invasive test the small bowel biopsies. The aim of this thesis is to evaluate different methods used in the identification (Chapter 2 shows improvements of serological mass screening programs for CD and chapter 3 adds knowledge to the relation between geno-phenotype of CD), diagnosis (Chapter 4 illustrates a diagnostic scoremodel that could prevent 58% of the usually performed small bowel biopsies) and follow-up of childhood CD (Chapter 5 investigates the decline and normalization of specific coeliac antibodies when being on a glutenfree diet). Furthermore, new strategies for the prevention of the disease are explored (in chapter 7 the rationale behind the primary prevention of CD is outlined, which is based on adjusting factors that contribute to the disorder might improve tolerance to the food allergens gluten). And chapter 8 describes a European multicenter study PreventCD that investigates whether it is possible to induce tolerance to gluten by introducing small quantities of gluten to infants, preferably whilst they are breastfed.Euro Diagnostica, Nutricia Nederland BV Phadia now Thermo Fisher Scientific Zorgverzekeraar VGZ, Nederlandse coeliakie vereniging, Leiden University Medical Center Celiac disease consortiumUBL - phd migration 201