At least three factors in the existing migration frameworks make them less suitable in Grid systems especially when the goal is to improve the response times for individual applications. These factors are the separate policies for suspension and migration of executing applications employed by these migratio frameworks, the use of pre-defined conditions for suspension and migration and the lack of knowledge of the remaining execution time of the applications. In this paper we describe a migration framework for performance oriented Grid systems that implements tightly coupled policies for both suspension and migration of executing applications and takes into account both system load and applicatio characteristics. The main goal of our migration framework is to improve the response times for individual applications. We also present some results that demonstrate the usefulness of our migration framework.