We report the large-scale production of V-HH antibody fragments, raised against the azo-dye RR-6, by the yeast Saccharomyces cerevisiae. The secretion efficiency of the V-HH fragments was correlated with their overall hydrophobicity. With a 15 m(3) fed-batch fermentation, 1.3 kg V(HH)s were produced. Purification was done by removal of biomass and product concentration. During induction, the specific production rate q(p) was 0.213 g.[kg dryweight](-1).h(-1).