A growing number of food manufacturers in western Europe are beginning to explore the commercial opportunities for foodstuffs containing health-promoting microbial food supplements (probiotics) and health-promoting non-digestible food ingredients (prebiotics). A prebiotic is considered to affect the host beneficially by selectively stimulating the growth and/or activity of one or a limited number of naturally present or introduced bacterial species in the colon, also leading to a claimed improvement in host health. Increasingly, probiotics and prebiotics are used in combination, this being termed a synbiotic (Gibson & Roberfroid, 1995). Throughout European history, fermented milk products in particular have been considered beneficial to health, but only in recent years has there been scientific support for these beliefs. Issues considered important to the continuing development of this growing market are proof of safety, proof of efficacy, consumer education, market positioning, price and appropriate health claims strategies. Until recently, much of the innovation in the use of probiotics and prebiotics has been in the dairy cabinet, with an ever-growing number and range of ‘health-promoting’ yoghurts and yoghurt-type fermented milk being made available to the European consumer, a market which is currently estimated to be worth in excess of $US2 billion per annum (Hilliam et al. 1997). However, prebiotics are beginning to find increasing application outside the dairy sector, particularly in baked goods. A key driver behind the broadening application of prebiotics has been the pro-active stance taken by key prebiotic suppliers such as Beghin-Say, Orafti and Cosucra. To date, market activity in probiotic- and prebiotic-containing foods has centred around three health propositions, namely improving general gut health, lowering blood cholesterol and improving the body's natural defences.