I admit that I don't get it. Why would somebody steal something they can borrow for free? Particularly when most of us have too much barely-used stuff as it is?

I hasten to add that the loss rate of library materials -- about 2%, according to our last inventory -- is surprisingly low. It's higher, I'm told, in retail.

But there are two kinds of materials that get hit pretty hard. The first is DVDs. DVDs are popular, accounting for 22% of all our checkouts. The most popular ones, the "Your Lucky Day" titles, have had loss rates from between a low of 22% to a high of 31% (depending on the branch). That means that almost a third of some of our DVD titles get swiped. It costs us thousands of dollars.

Libraries have tried to come up with a host of strategies. There's the big DVD dispenser, as seen at McDonalds. But we have way too many DVDs to make that practical.

There's the big security system approach: big gates, and magnetic strips or tags. But that's expensive, and the experience of many libraries suggests that not only do many kinds of tags make it harder to play the DVD, it really doesn't solve the problem.

There's the "ask for it at the desk" model, where staff fetches it for you. But that leads to big slowdowns at the checkout line, and more staff than we can afford.

So we've settled on an approach that we hope will provide a minimum of fuss, but a maximum of result: locked cases.

Our DVDs come in slim plastic cases. Effective last week (you probably saw the signs all around the checkout areas) you have one more step for DVD self-checkout -- slide the case through a little grooved device, called a decoupler. It looks like a big, black, knife sharpener.

The side of the case that opens now has two little icons: a green "unlocked" picture, and a red "locked" picture. Slide the case through the decoupler one way, and it locks. Slide it the other way, and it unlocks. It's easy, and you can tell at a glance if it worked.

But if you don't do it, the case really can't be opened without destroying it. And destroying it will probably destroy the DVD, too.

We can't make theft impossible. So we're trying to make it inconvenient.

The locked cases will involve only two kinds of library materials: DVDs and our much smaller collection of video games.

We started this one last year. There's a lot of research that there are in fact some benefits to gaming. Of course, there aren't as many benefits as there are to reading, in my judgment. (Sniff.) But we won't have as many games as we do books, either.

We did a trial last year, and our titles -- for PlayStation 2 and Xbox -- went out like hotcakes. In fact, they were rarely on the shelf.

Unfortunately, some of them got snapped up so fast the people taking them neglected to check them out. So round two of our experiment will attempt to hang onto them a little better.

In case you were wondering, our video games are rated E and T only (Elementary and Teen). We're not buying M or AOs (Mature, Adult Only).

My apologies for another small step in the attempt to get public materials home for viewing. But that's the way crime works: a few people inconvenience us all.

The payoff, in this case, should be that you have more to choose from.