High availability, scalability, agility and fault tolerance are aspects of inter-organizational workflow management systems that now represent important next focal points in the ongoing maturity of the research stream. Web services can enable an organization to expose public processes of internal systems in a way that can support inter-organizational workflow. Enforcing standards designed to support fault tolerance in the processes exposed through web services by interorganizational workflow participants will likely include provisions for check-points, recovery from logs and the passing of messages designed to facilitate early failure detection. This paper provides literature-based foundations for standards related to fault tolerance aspects based on similar fault tolerance issues discussed in the mobile computing literature. These foundations are extended to formalized failure cases for the workflow context. The appendix discusses the design of our testbed system intended for investigating candidate fault tolerance algorithms for potential inclusion in standards.