Condensin plays crucial roles in chromosome organization and compaction, but the mechanistic basis for its functions remains obscure. We used single-molecule imaging to demonstrate that Saccharomyces cerevisiae condensin is a molecular motor capable of adenosine triphosphate hydrolysis-dependent translocation along double-stranded DNA. Condensin's translocation activity is rapid and highly processive, with individual complexes traveling an average distance of >= 10 kilobases at a velocity of similar to 60 base pairs per second. Our results suggest that condensin may take steps comparable in length to its similar to 50-nanometer coiled-coil subunits, indicative of a translocation mechanism that is distinct from any reported for a DNA motor protein. The finding that condensin is a mechanochemical motor has important implications for understanding the mechanisms of chromosome organization and condensation.