Celiac disease is an intestinal inflammatory disorder that occurs in genetically predisposed individuals and causes intolerance to wheat protein gluten and related proteins (prolamines) that are contained in barley and rye. Histologically, the small bowel mucosa in celiac disease shows villous atrophy (lost of villi), crypt hyperplasia and lymphocyte infiltration. To allow better understand the histological damage that occurs during mucosal changes Marsh proposed a series of stages to aid diagnostics: Marsh I represents lymphocytic enteritis, Marsh II represents lymphocytic enteritis with crypt hyperplasia, and Marsh III represents partial (a), subtotal (b) and total (c) villous atrophy. These changes are accompanied by a gradual increase in the number of T cells and activation of immunoregulatory counteractions in the diseased mucosa. The March 2011 special issue on celiac sprue and mucosal immunity presents some of the latest advances in celiac disease diagnostics; the web focus further expands our understanding of this inflammatory disorder through a collection of recent articles from across Springer Nature.