The maximum productivity of beta-glucosidase by Saccharomyces cerevisiae recombinants under the control of GALI promoter was 100 IU l(-1) h(-1). The highest productivity of beta-glucosidase by a S. cerevisiae recombinant was 16-fold more than that supported by Cellulomonas biazotea. The recombinants also co-produced ethanol from cellobiose: maximum product yield and productivity were 0.5 and 1.1 g ethanol g(-1) cellobiose and g ethanol l(-1) h(-1), respectively.