The document has introduced the open provenance model, consisting of a technology-independent specification and a graphical notation, to express causality graphs representing past executions. In the future, we will define a serialization format for this model. We will also specify protocols by which provenance of artifacts can be determined, and protocols for applications to record descriptions of their execution. We invite teams that have defined their own provenance model to establish whether their representations can be converted into this model and vice-versa.