The spindle checkpoint is a surveillance mechanism that ensures the fidelity of chromosome segregation by inhibiting anaphase onset until all chromosomes have established stable bipolar attachments. Here we describe a number of protocols that can be used to assay the ability of budding and fission yeast cells to (1) establish and maintain a spindle checkpoint arrest, and (2) segregate chromosomes efficiently upon recovery from mitotic arrest. We focus on experimental detail of the budding yeast protocols, but also point out important differences between budding and fission yeast assays.