The standardization of Business Process Management and workflow technology has been discussed for more than ten years. Several standardization bodies have proposed specifications for different aspects of Business Process Management. The five bodies that have gained the most attention in this context are WfMC, OMG, BPMI, W3C, and OASIS. BPEL is gaining increasing attention as a potential standard for the definition of executable business processes based on web services. This paper gives an overview of standardization efforts in the area of business process execution, of the main concepts of BPEL, and of its support in practice.