1. Computer apparatus for managing revisions to engineered products, comprising: a data store holding at least one asset for forming an engineered product; a revision manager tracking changes made to each asset, for a given asset the revision manager providing together in a certain screen view to a user (a) indications of changes made to a working copy of the given asset relative to the given asset as held in the data store, and (b) indications of changes made to the given asset in the data store relative to the working copy of the given asset.