In fission yeast  Schizosaccharomyces pombe,  initiation of meiosis is repressed by Pat1 kinase. This protocol describes how ectopic inactivation of the temperature-sensitive Pat1-114 kinase in G 1 -arrested  h -   / h -   diploid cells carrying  mat1-Pc  induces a highly synchronized commitment to and execution of meiosis. Haploid or diploid  pat1 -114 mutants without  mat1-Pc  can also be used for convenience, although less synchrony may be attained compared with induction using true diploids. An essentially identical protocol can be used for induction via inhibition of genetically sensitized Pat1 kinase by ATP analogs.