Weldon Wirick III, a senior vice president with S&K, said his company's stores have had more trouble with burglars but have suffered their share of robberies. In cases where the Lexan windows didn't stop the "smash and grabs," S&K has reluctantly put bars in the windows, he said.

Ronnie Adolf, owner of Adolf jewelers, described how two clean-cut men came into his store near Regency Square mall in February, drew handguns, cleaned out his stock, and locked customers and employees in bathrooms and storage rooms.

The robbers who hit Adolf's store appeared fairly professional, Adolf and police said -- not the average robber. Adolf has since hired an armed guard, but many robberies can be deterred by simpler methods, the merchants were told.