Lately I have been poking around workflows to better support translators. The localizer module suite has no built in workflow support, and i18n module suite has a very simple and limited built-in workflow, so for complex workflow requirements, people need to look elsewhere. Luckily, respected members of the community maintain the workflow and actions modules, which allow for setup of more complex workflows.
Translators are some kind of content editors, but if you need real control over what they can do, you would not allow them full content editing privileges. Workflow based permissions help here, so you can hand out editing permissions to translators even in draft phases of their documents, while would only allow them to see documents to translate, when those are approved (but might not be published yet). As with any workflow setup, actual requirements depend on your needs, and workflow permissions do help any other use case with workflows, not only translators.
So I approached Mark Fredrickson with a list of possible workflow permission modules I looked at. Unfortunately those modules were either incomplete, outdated and/or only marginally applicable. We agreed that Earl Miles' workflow_access module was a good candidate, but it was part of the discontinued na_arbitrator package (it's core functionality being included in Drupal 5). So I went on, grabbed the module, looked up API changes, fixed UI glitches, tested the updated code with sample workflows, and sent in the updated module to Mark via the issue queue as he requested. As a result Workflow 5.x-1.1 shipped today with workflow_access included!
On a related note, I announced my XLIFF Tools module, also developed as part of my thesis work earlier this month in the Internationalization Drupal Group. So it was a natural step to make XLIFF Tools work better with workflows. I am not entirely sure I made the best decision, but I decided to add an action to xliff.module which allows you to limit the import and export features to certain parts of a workflow. That would not bother the user with XLIFF importing and exporting controls, if a document is complete (if that is how you set up your workflow), and would show the import or export widget relevant in the appropriate context of the actual workflow.