It's late in March. The sun is -- finally -- shining. It's time to throw a party.

And 48,000 people are coming to dine.

Are the folks at Oriole Park at Camden Yards concerned, with less than a week to go to Opening Day on Monday? Nah. They've been preparing for this moment since February.

"Just like the players have spring training, we have spring training," says Bernhard Kloppenburg, group manager of ARA Leisure Services, which runs all the food service, concessions and shops at the ballpark. The goal this year, he says, is "a seamless sense of service."

"We call it the world's largest dinner party," says Charles Steinberg, Orioles' public affairs director.

The 2,000 or so food service employees are being taught alcohol awareness and intervention. Ushers will learn how to direct people to various concessions. Menus are being tested and provisions are being gathered and stored. Paper goods are being neatly stacked on shelves. Restaurant and bar spaces are being redesigned. Shops are being stocked.

Beer has been arriving for more than a week. It's stored in underground coolers -- whimsically named things like "Hugh" and "Charlie," after people from the ARA organization -- and runs through 5 miles of pipe to some 70 or 80 venues throughout the stadium.

"I have the capacity to hold 2,700 kegs in this building," says Bob Harting, director of procurement for ARA. "On a good day -- in August, when it's really hot -- I'll probably go through about 175 a game. For Opening Day, I'm anticipating 400, maybe 500 kegs. Basically, it's five or six games at the most."

"This is where I keep all my canned beer," he says, opening a room-sized cold locker. "This handles approximately 45 pallets of beer and each pallet has 98 cases on it. And each case has 24 cans. This will hold me over for approximately a home stand. Up to 10 games."

How about hot dogs? "My initial order is 40,000 pounds . . . that will last me approximately four to five games." He leads the way to another walk-in freezer, where cases of hot dogs are stacked to the ceiling. "By Opening Day, I will have 40,000 pounds of hot dogs in this room."

And popcorn. There's a whole room just for popcorn. "We have three industrial poppers. When we get going during the season, we pop from 6 in the morning till midnight, every day. Each bag is approximately 8 pounds of popcorn, and I go through 200 a game." Fans will get a little extra nudge to buy popcorn this year: The vent right above the poppers has its outlet right in front of one of the delis. "The popcorn for Opening Day, we will probably start on Wednesday or Thursday. . . . I'm going to have at least 350 bags. Opening Day is always a larger event -- everybody knows what Opening Day is in Baltimore, it's one of the largest events in baseball."

And soda. "My opening order for bag-in-a-box is over 1,100. And each bag-in-a-box produces 30 gallons of soda. It's five gallons of syrup and once you put it in the system, it mixes out to 30 gallons of soda."

But the fan who strolls in and buys a dog and a beer on the way to his seat is only a speck in the food universe at Camden Yards. The empire stretches from the offices and vast storage rooms under the stadium to the Eutaw Street promenade to the top floors of the B&O; Warehouse. Besides the concession stands -- such as Grille Works and Fan Fare -- there is food service to the suites and elsewhere on the Club Level, there are catered events in the warehouse, and there is fine dining in the Camden Club. While activity picks up in the spring, there are perhaps 100 to 200 events held at various sites in the park throughout the year.

"Last night we did an unveiling of the new suite menu, and presentations for all the suite owners on the level of service they can expect this year, today we have a plated, sit-down luncheon for 240 people, as well as a trade show for 1,200," says executive chef Russell Szekely. "That's typical of our banquet business during the off-season. There's a lot going on behind the scenes with or without baseball. Of course we're gearing up for a strong season. In season, this kitchen runs 16 hours a day. We provide catering to the suites, banquet facilities, and of course items like Boog's [Boog Powell's] barbecue, and [Tom] Matte's ribs, crab cakes for the stadium, this is a full-scale operation. All our production is fresh and delivered from our stadium kitchens to the site the day of the event.

"It's a wide variety of items and a wide variety of menus, so any fan that's coming to the ballpark can find something that suits their taste," he says.

Upstairs, and upscale, at the Camden Club, that taste might run to smoked salmon lasagna. "We make fresh, homemade, whole-wheat pasta and cut it into rounds, and layer it with cherry-smoked salmon, different cheeses, grilled vegetables and spinach," says club executive chef Chris Linzey. "And crab cakes are always a big hit."

Hot dogs and beer are the two most popular food items sold at the park (baseball caps are the most popular non-food item), Mr. Kloppenburg says. But barbecue sandwiches from the stand manned by Mr. Powell, former Oriole first baseman, is increasingly popular. "Boog's giving them a run for their money," Mr. Kloppenburg says of ARA's popular food ambassador.

"We realize that fans who work downtown want to come over here after work and have dinner, and afterward enjoy the ballgame," says Charles Steinberg. Oriole Park is just entering its third season. "We know people came because the park was new," he says, and the goal of the Orioles under new owner

Peter Angelos is to sustain the excitement. "There's something special about the aroma of the ballpark. Food's an important part of that."

"It's a happening, not just a baseball park," says Mr. Kloppenburg, whose background is in airport, racetrack and convention center services, and who's been in Baltimore only a few weeks. That's been long enough for the enthusiasm for the award-winning ballpark to have become second nature to him. "The charisma we've been able to put together -- nobody can beat that. I've seen people come in and just walk around looking at the park."

There are some changes at the park this year. Suite owners won't be seeing any more black plastic dishes or trays; they've all been replaced with wood and china. And club level fans won't have to go downstairs to get Boog's barbecue; there'll be a small Boog's stand on the club level. Pastimes cafe has been redesigned to be more "fan-friendly;" people who just want to grab a hamburger and a Coke can go through an express line instead of winding their way through the pizza and deli sections. And Bambino's pub is being redesigned to make it more lively -- there will be games and Bambino's apparel that fans can buy.

Vendors in the stands will be selling Copperidge chardonnay and blush wines. There's a new stand on Eutaw Street selling products from local microbreweries. Ice tea will also be available and there will be a number of coffee kiosks, where people can get the specialty coffee drinks that are so popular these days.

Some of the changes are based on brainstorming sessions between the Orioles and ARA. Some are suggestions from fans. It's likely that more formal attempts to gauge fan reaction will be sought this year, perhaps by messages on the scoreboard during games, with an address where people can write.

"There's an irony to the bigness" of the whole operation, Mr. Steinberg says. "You're serving 48,000 people, but you're cooking hot dog by hot dog. . . . These are 48,000 guests in our home, and we want the food to be good."