SMC complexes are essential complexes involved in chromosome structure and segregation. The cohesin complex holds sister chromosomes together after replication and the condensin complex compacts the chromosomes at cell division. Both are important for the accurate segregation of chromosomes into the two daughter cells. The related Smc5/6 complex is also essential and conserved from yeast to man. It is required for homologous recombination, rDNA stability and telomere maintenance. In fission yeast we have shown that like the RecQ helicase it is required to resolve recombination structures at broken replication forks (Ampatzidou et al, 2006). Recently we identified a new role for this complex in stabilising stalled replication forks, which is important for how replication is restarted (Irmisch et al, 2009). The Smc5/6 complex is also required for cohesin removal after replication is stalled (Outwin et al, 2009). Our current work focuses on the roles of the Smc5/6 complex in DNA repair, recombination and replication and the implications of these roles for genome stability.