Workflow management in the grid era faces many challenges both related to workflow modeling and workflow execution. To deal with the challenges, the paper argues that the traditional process-driven workflow management paradigm should be replaced by a goal-driven one and proposes a corresponding implementation approach. The contributions of the paper are as follows: (1) a concept of process pattern is put forward that is an effective means not only for procedural knowledge representation and sharing but also for expertise exchange between domain experts and computer scientists; (2) based on process patterns, a goal-driven workflow framework is designed that incorporates semantic Web technologies and artificial intelligent (AI) planning techniques and that can (semi-)automatically generate a workflow on the fly according to the requirements of users and the running context.