Hybridization studies based on the prototrophic selection technique, involving the use of auxotrophic mutants of strains of five accepted species of the genus Schizosaccharomyces, are reported. Intrastrain recombinants were recovered in five out of six tested parental pairs. Interstrain recombinants were recovered from crosses involving strains of S. japonicus and strains of S. pombe. No recombinants were recovered in 62 interspecific crosses involving all possible combinations of the six representatives of the genus.