"Giant cell" production by C. albicans cultured in the presence of substances belonging to the pentitol family is described in this study. After two days of incubation, at pentitol concentrations ranging between 0.1 and 20 mg%, the production of very large, frequently multibudding cells became evident. Their number increased with time, in some cases reaching 20% of the culture cells and their size could exceed 25 mcm. Comparisons with other sugar/alcohols and with other Candida spp. are presented. A possible explanation of this observation is consistent with an accumulation of pentitol catabolites in the yeast cytoplasm followed by an increased osmotic strength and cell swelling.