We used the model of faecal microflora under continuous flow culture (CFC) conditions to study the growth of Candida albicans in mixed cultures. The development of Candida is usually limited by the high germ counts of aerobic and anaerobic bacteria. Candida growth in faecal flora could be obtained neither by the continuous inflow of C. albicans CFC monocultures nor by intermittent input of highly concentrated suspensions of C. albicans into the system. If the system was run under aerobic conditions development of C. albicans could be observed. After some days, however, the faecal flora again suppressed further development of the yeasts. Only marked destruction of the aerobic and anaerobic microflora by antibiotics resulted in growth or overgrowth of Candida albicans.