Kay is a 48-year-old grandmother who has always been active in her church, often hitting up friends for one charity or another. Lately, she has been thinking about employee theft.

Kay has time for reflection. She is serving a four-to-eight-year sentence for forgery. She admitted to stealing more than $400,000 from a company that had revenues of about $14 million. "Given the right circumstances," says Kay, "anyone is susceptible to doing it."

Kay had been working at the company for nearly eight years, in charge of both accounts payable and receivable. In 1980, she started writing checks to herself. If the company owed, say, $50,000 to a supplier of light bulbs, she would enter a $60,000 payment in the books. Then she would write an extra $10,000 check to herself. Inventory records were so inaccurate that nobody could tell whether the company had $50,000 or $60,000 worth of light bulbs.

It all started, Kay says, when her daughter's marriage failed and her son needed financial help. She put her daughter through nursing school and furnished her son's house. But one day she told her husband what she'd been doing. "I couldn't live with it anymore," she says.

Not so for 22-year-old Maria. In 1985, the former high-school honor student started working at a sandwich shop. The store's owners were never around. At first, she would take $5 from the register to buy beer. Then $25 for partying.

But a new owner took over, one who balanced the books himself. About a month later, he fired Maria. Furious, she went on a daylong drinking binge. The next night she decided to go to the store and make herself some sandwiches. She entered through an unlocked door. Just then, she heard a voice. "I thought you'd be back," boomed the new manager. Four squad cars appeared. Though Maria had stolen $800, some of which was recovered, the owner didn't press charges.

Steve (not his real name) wasn't so lucky. In 1986, he got a sales job at an auto-parts store. It's only for a short time, his bosses told him; we're grooming you to be a management trainee.

Five months later, having heard nothing more about it, Steve decided to take revenge. The store's shoddy inventory records often listed certain parts as not being in stock when they were on the shelf. At night, Steve would search for such parts; then he'd do the paperwork as if a customer had returned them.

Over a few months, he took $5,000.

Then his bosses noticed that the same part had been returned two days in a row. Digging deeper, they also found that Steve had far more returns than others. Now, he is serving a year-long prison sentence. "I was the last person they ever would have suspected," he says.