The bottom line is that you probably can't ensure it's deleted. Consider this: I have at least two backup mechanisms I use regularly (Dropbox, Time Machine) an

The bottom line is that you probably can't ensure it's deleted. Consider this: I have at least two backup mechanisms I use regularly (Dropbox, Time Machine) and I don't even think about them at this point. Even if you watched him delete it, it's pretty likely that data already exists outside of his laptop, if he's even reasonably diligent about his machine. So you're left with a few options: * Trust If you're firing him for a good reason, and can validate that reason in his mind, you can choose to trust that he won't be a douche * Trust with seeds Before firing make sure the data has something uniquely traceable to him. Data that only his export gets; dummy users, dummy data, something steganographic so if your trust is violated you can identify the breach source. Your options are limited, AFAICT. Once data exists in the wild it's essentially impossible to maintain any semblance of control. Your only real hope is that he's honorable. Even in the worst of circumstances I'd never breach trust in that way. Especially when there are much more insidious, passive-aggressive, entertaining ways to bring down a company.