My rule of thumb: Never, ever go to HR with an issue that is not clerical in nature. If you have an issue that involves things you'd expect HR to be responsible

My rule of thumb: Never, ever go to HR with an issue that is not clerical in nature. If you have an issue that involves things you'd expect HR to be responsible for (safe workplace, abusive behavior, etc.) you will be shafted. Simple numerical issues ("Hey, you paid me too much last month") will often be handled efficiently. I'd make an exception for blatantly illegal behavior, in which case I'd report the issue anonymously. HR is not there for employees.