1. A model edit control system for controlling editing of a data model, the model edit control system comprising: a model repository manager for allowing multiple users to copy a stored model stored in a repository for executing actions on multiple model copies in parallel; an action log manager for crating a model action log for tracking actions executed on the stored model, and for creating a current action log for each model copy to record actions executed on the model copy; and a model merger manager for merging the model copies into the stored model in the repository by playing the actions in the current action log against the stored model.