Traditional sourdough bread resorts to spontaneous fermentations leading to natural selections of microorganisms, mainly yeasts and lactic acid bacteria. Such microorganisms are essentially beneficial to humans and, concomitantly, inhibits propagation of undesirable microbiota. Sourdough fermentation was probably one of the first microbial processes employed by Man for food production and preservation. Sourdough bread stills widely manufactured at farm level across Europe and worldwide and is highly appreciated by consumers for its distinct flavour, texture and healthy attributes. Through a bottom-up approach, this COST Action network brings together a multidisciplinary group of scientists and SMEs/LEs dedicated for many decades to study cereals and sourdough technologies. SOURDOMICS will exploit sourdough technology through entire value chain: from sustainable cereals’ production, through fermentation processes’ exploitation, to by-products’ valorisation in circular economy.