"It's not so much what [a restaurant] needs tobe successful in the Square, but what it needs tobe successful anywhere," says Christopher G.Glionna, the general manager of the Harvestrestaurant, a Square fixture which will reopenthis week.

Service is key, he says.

Owners and managers must balance severalfactors.

Rent ranges $40 to $100 per square foot forSquare restaurants, depending on the type ofrestaurant, whether it serves alcohol, how manyseats there are and other factors, according toCindy Miller, associate executive director of theHarvard Square Business Association.

Harvard Square is one of the highest rentdistricts in Cambridge, but restaurants also haveto pay for food, utilities, staff and evenentertainment.

The goal of a good restaurant is to keep foodand staff costs below 60 percent of gross revenue,says James Miller.

"Every schmuck thinks they can start arestaurant. They think they'll be like Rick inCasablanca," he jokes.

"It's like a Venus flytrap. It's morecomplicated than it seems to be. The barriers toenter are very low--rent the place, get someequipment. You don't need to launch a satellite,"he says.

Trost agrees.

"Sometimes people are starry-eyed aroundrestaurants, but a restaurant is not easy to run,"she says.

"It takes a lot of commitment on everybody'spart. It's very difficult to make a profit inrunning a restaurant," she says.

To Be the Best

Beyond simple staying power, restaurants in theSquare aim for the top.

"Harvard Square is one of those `If you canmake it there, you'll make it anywhere'[environments]," Cindy Miller says.

"If you don't do it right, there's alwayssomebody else waiting to welcome your customer,"she adds.