Accurate chromosome segregation is dependent on a specialized chromosomal structure, the kinetochore/centromere. The only essential constituent of the S. cerevisiae kinetochore established today is CBF3, a multisubunit complex that binds to S. cerevisiae centromere DNA. Therefore CBF3 and its four components, Cbf3a, Cbf3b, Cbf3c and Cbf3d, will form the centerpiece of this review. In addition, we will describe proteins that are putatively involved in kinetochore function specifically in the context with CBF3 interaction. Furthermore, we discuss the role of the S. cerevisiae kinetochores in a putative cell cycle checkpoint control and in microtubule attachment.