Giving your employer two weeks' notice when quitting a job is a longstanding "best practice" for U.S. employees. Today, however, not everyone agrees that the convention remains relevant. Some business writers advise matching your notice to the particular circumstance at your company, while one writer advises giving employers no notice at all.

Two Weeks -- Maybe

Allison Greene, a business writer for "U.S. News," accepts the possibility of giving longer notice, but writes that in some circumstances less is better. If your employer has a history of appreciation for longer notice, and you are able to delay your departure without jeopardizing your new job, then she advises, giving more than two weeks' notice may be appropriate. However, if employees in your company who give notice are quickly shown the door, give short notice, which could be a week or even less. Suzanne Lucas, writing in "MoneyWatch," notes that when the circumstances deteriorate sufficiently -- when your employer, for instance, is telling you to do something illegal -- you may have to leave immediately.

Longer Notice

Some employment advisers still recommend at least two weeks notice, and even more notice if you may be hard to replace. If you have an employment contract and it specifies a longer notice period, that's the notice to give. When you signed the employment contract, the longer notice period became your legal obligation.

What's Good For the Goose...

One relevant issue not many business writers bring up is how much notice an employer gives to employees being terminated. Jim Carlini, writing in "WTN News," notes that many employers give no notice at all -- you may get a fax or an email informing you that you're fired, soon followed by a security guard who ushers you out of the building. If that's the employer's notice, he wonders why an employee is expected to give more. He suggests that even from the employer's perspective, shorter notice may be better. When an employer ushers employees out the moment they are terminated, it's not necessarily mean-mindedness. Carline cautions that if terminated employees are allowed to hang around, they may cause problems. While the circumstances are slightly different for an employee leaving voluntarily, it's still a good idea, he writes, to get someone out of the office quickly once it's clear they're no longer a permanent member of the team.

Benefits of Adequate Notice

Even when you have no legal obligation to give a specific advance notice, it's still a good idea to think about what your employer might appreciate. In most cases, you may not want to give more than two weeks notice, but giving less may cause hard feelings. When someone calls for a reference, you hope for a good one, which giving adequate notice helps assure. Although these days employers may no longer feel safe trash-talking former employees, a human resources executive at the company you've left may find a way to send another HR exec a coded signal of "restrained enthusiasm" in retaliation for a no-notice exit. That could cost you a job some time in the future.