Few people have given much thought to the origin of mushrooms. Most know they are a fungus but are quite happy to enjoy their culinary attributes without searching much deeper into their life-cycles. In fact, mushrooms arise from a microscopic, branching, thread-like mycelium that itself comes from a spore. Asexual reproduction between two mycelia leads to production of a ‘fruit’, such as a mushroom. Mycelium is rich in vitamins, minerals, enzymes and other substances and has become commercially important as a food supplement. In addition, many of the enzymes found in mycelia break down hydrocarbons, making them an interesting option for bioremediation of oil spills. While mycelium-related products encompass a variety of different categories, mushrooms have the largest market share in the European market. Raw materials are susceptible to infection and threaten stable, reliable and safe production. European researchers sought to ensure safe hygiene and thus enhanced yield and quality of product to meet growing demand. EU funding of the ‘Development of an energy efficient bulk sterilisation technique for the production of mycelium’ (BULK Substrates) project provided the opportunity to do so. In particular, scientists focused on sterilisation for safe, cost-effective and low-energy bulk production of uncontaminated mycelia. The consortium produced a prototype system for solid-state fermentation (SSF) of a variety of organisms. The BULK Substrates system was suitable for mycelium of higher fungi such as edible mushrooms, lower fungi such as those used in biocontrol of crop pests and even some bacteria. Intellectual property rights to the BULK Substrates system are owned by the consortium’s small and medium-sized enterprises (SMEs) who have agreed on utilisation and commercialisation of the technology. European producers may now be poised to meet increasing worldwide demand for mycelium-related products.