Answer: In a perfect world, yes.

The problem is, we don't live in perfect world. In fact, we live in a commercial world where anything and everything could be sold. Take the case of cell phone service companies. Not only will they milk your money in the form of monthly bills or prepaid credits, they could sell their database of subscribers to reverse lookup companies. Not that there's anything wrong with it.

We're just saying. If you want to know who your husband has been talking to in the bathroom, you better pay the price for finding out who. (You couldn't help but take note of the unregistered number after faintly hearing him moan while you were at the door listening.)

Mobile phone numbers are typically excluded from the directories and directory assistance services. Someone once started a furor against the proposal to index cell phone numbers into a sensible A-to-Z directory. The mantra was that having a directory of this kind would set off a telemarketing frenzy that went straight to the telemarketers and none through the gatekeepers.

But of course, that kind of revolt against an organized cell phone directory has not stopped reverse lookup companies from offering their own directories that you can access for a small fee. You can admire such companies for maintaining updated databases of cellular phone subscribers – the numbers often number in the millions.

Some of them offer a free search to make you see if they've got the information you need. The very good ones offer charge as high as $25 per search. Other companies also offer unlimited searches for a one-time fee, some as high as $59.

If such type of companies is not your thing, there are, of course, other remedies. Consider technology as your best friend. Do a Google search on your telephone number and hope to God a profile is going to pull up, with a picture (with your husband in it) to boot.

You could also sign up with some free cell phone directory websites. But the information on these websites are not nearly as good as those that you pay for, precisely because the information on there are those that have been volunteered by their members.

Still, there are reverse lookup companies that purport to provide a free service. But the real score but it's tough to find ones that really give out free information on the numbers that you are trying to look up. You will inevitably find yourself hopping from one service provider to the other, unlike when you sign up with a premium company and find all the information you've been looking for.

With a paid reverse lookup, you would typically be provided with information on the owner of the cell phone number such as the name, address and background information.

If your husband is taking too long in his cell phone conversations and hiding behind the call of nature when he's talking on the phone (and you heard that faint moan behind that bathroom door), then it's time to do some detective work. Do a reverse lookup on that mysterious number.