Observing the dynamics of a specific chromosome locus in living cells can provide important information as to the molecular mechanisms underlying events such as chromosome segregation, homologous chromosome pairing, chromosome arrangement, and gene expression. The  lacO /LacI-GFP system provides a simple and useful method in which a chromosome locus is visualized by inserting  lacO  repeat arrays and then expressing an LacI-GFP fusion that specifically binds to the  lacO  sequence. This system has been adapted for use in  Schizosaccharomyces pombe  by expressing the LacI-GFP under a promoter of the  dis1  +  gene. Furthermore, a two-step integration method has been developed that ensures high-efficiency integration of  lacO  arrays to a desired target position.