Process migration is an important tool on NOWs (network of workstations) for load-balancing and high availability. In this paper, the authors present a log-based approach to provide process migration for parallel applications. Because this approach is implemented on top of PVM (parallel virtual machine), it is transparent to users and portable. This approach has been used in the ChaRM (checkpointing-based rollback recovery and process migration system) system. The experiments show that the overhead is low.