Condor is a open-source, specialized workload management system for compute-intensive jobs. Like other full-featured batch systems, Condor provides a job queueing mechanism, scheduling policy, priority scheme, resource monitoring, and resource management. Users submit their serial or parallel jobs to Condor, Condor places them into a queue, chooses when and where to run the jobs based upon a policy, carefully monitors their progress, and ultimately informs the user upon completion. Condor also contains mechanisms to submit jobs to grid-sites and supports many different grid toolkits. It is developed at the University of Wisconsin-Madison's Department of Computer Sciences. WWW: http://research.cs.wisc.edu/condor/