It's checkout time at the Ramada _ which means it may be time for the hotel to check whether you have stolen any of its property.

The bellhops at many Ramadas have been told that whenever they help carry out a guest's luggage ``to make sure the clock radio is still there and the hair dryer is on the wall,'' says Bill Keeble, a vice president for the Ramada chain's parent company. He insists they are as discreet as possible. ``You wouldn't even know they are there.''

Forget about bolting down televisions or nailing paintings to the wall; hotels as widely known as Hilton, Marriott and Sheraton have moved to a new level of sophistication to guard both small knickknacks and costly objects in a hotel room. Some of them are installing sensors in minibars or are using room keys that record a guest's comings and goings. Others are not only training, but rewarding, employees for snooping. And then there is the Comfort Inn chain, which recently starting stenciling signs beneath the paintings in some of its rooms; if guests take down a painting, they find the words ``Artwork Missing'' on the bare wall.

It has come to all this, hotels say, because petty theft is turning into grand larceny. Analysts estimate that the industry is losing more than $100 million a year to thieves.

``People think they're allowed to take anything just because they're staying in a room,'' says Shanlee Smith, executive housekeeper for the famed Hotel del Coronado, near San Diego, where guests last year stole half of the hand and bath towels _ more than 7,000 in all. The Holiday Inn chain figures that a towel is stolen every 11 seconds, according to a spokesman.

Some elegant hotels, particularly plagued by thefts of items imprinted with their famous names, have been removing such identification from towels and the like. But perhaps the most surprising antitheft tool used by hotels has been alarm-triggering strips. They resemble a label and are stitched into towels, sheets and pillowcases. One of the first hotels to use them was the Chicago Midland Hotel, a midprice property frequented by business travelers. For several months, departing guests were asked to walk through an exit door framed with sensors. Eventually, the Midland says, it gave up on the system because too many strips were coming out in the wash. But at least a half-dozen hotels are still using them.

``I suppose it's a little extreme,'' says George Usher, general manager of the Studio Lodge Hotel, a 107-room, low-budget property in North Hollywood, Calif. ``But it's saved me thousands of dollars.''

At the Sheraton New York Hotel and Towers in Manhattan, the battle against petty crime has turned to a combination of high-tech gadgetry and employee tattletales. According to hotel security officials, the 300 maids have been trained to peek into rooms, even if the guest is still packing up. The maids won't confront anyone, but they are supposed to report any major missing item to the front desk. As an incentive, the hotel says it has occasionally rewarded a maid with a $25 bonus or a free dinner.

``It's not Big Brother,'' says Vince Russo, director of security. ``It's just making room attendants more responsible'' for the room.

Like many hotels, the Sheraton New York has also had to grapple with a nagging issue _ checkout flow. Because they don't know when a guest checks out for good, hotels normally can't prove who really stole a knickknack. But the Sheraton New York says it has solved that problem with a hand-held device that identifies which keys were recently used to get into a room. (Dubbed the ``Interrogator,'' the device is also widely used to investigate break-ins.)

``It really cuts back'' on disputes with guests, says Chad Callaghan, senior director of loss prevention for Marriott, which uses a similar device.

Nevertheless, and not surprisingly, most antitheft measures taken by hotels haven't been well-received by many travelers; and opinions are divided in the industry over whether any of these steps is worthwhile. ``I think you're just alienating guests, which is the worst thing a hotel can do,'' says Morris Lasky, chairman of Lodging Unlimited Inc., a hotel consulting firm in West Chester, Pa. Some analysts point out that while $100 million in petty theft is no small number, it is nonetheless tiny compared with the industry's revenue, which last year totaled $67 billion.

Still, hotels are more likely these days to add a charge for a stolen item onto a guest's credit card _ even after the guest has departed. They are also monitoring minibars more vigilantly. Recently, New York writer Caroline Bollinger says she was both surprised and ``a little irritated'' to find a $25 charge on her credit-card bill _ and a letter from a Ramada resort in Miami Beach informing her of six beers she drank from the minibar without paying.

``I think it was somewhat petty,'' says Ms. Bollinger, who admits to drinking the beers. ``They could have told me before I left.''

But hotel officials say they just won't tolerate unpaid minibar bills and most missing items anymore. Marriott says it may charge for anything missing that is valued at more than $30. And the luxury Cheeca Lodge in the Florida Keys automatically bills guests for missing beach towels _ at $15 a pop. ``I don't think it's ethical (taking a towel),'' says an unapologetic Pat Rzempoluch, the hotel's controller.