"Unfortunately, dishonest employees are everywhere, and I certainly would not consider myself a 'whistle-blower' in the workplace. If I found that a co-worker was stealing or doing anything to harm the company, I would approach them directly to ask what was going on. There is a good chance of the situation being a simple misunderstanding. If it wasn't a misunderstanding and the co-worker was outright defiant with their damaging actions, then I would bring it up, in a professional manner, to the appropriate parties."