With checkout counters finished on Day 1, a FedEx van arrives by noon with two to five Model 4694 point-of-sale terminals from IBM. Setters such as Rambus take charge of the machines, unpacking them and planting them on counters.

The registers come loaded with a simple piece of command-line-driven sales-tracking software from Triversity in Toronto. A graphical application was voted down a few years ago partly because the Microsoft Windows operating system was deemed too slow and complicated to reboot after a power outage—a frequent problem for Dollar General in rural areas in the South and Midwest.

The IBM machines are capable of e-mail but Dollar General doesn't use it. Instead, managers broadcast voice mail to employees on the company's private telecommunications system from Sprint.

Today the crew organizes a stockroom for excess inventory that will inevitably accumulate as distribution centers truck goods—sometimes too many—out to stores every week. The room is usually in the back of the store, behind a wall of shelves full of laundry detergent (Arm & Hammer, $4; Tide with Bleach, $5). "Chemicals" are one of Dollar General's biggest sellers.

A manager's office also takes shape. Hooks are screwed into the walls of Ethel Longway's small office in Whitesboro to hold the 15 clipboards that will track employee contact information, store sales, cash deposit logs and the arrival of items as varied as sewing notions and Little Debbie snack cakes. Longway's spartan gray-metal desk takes up most of the space.

Dollar General operates top-down, with senior executives at headquarters controlling nearly every aspect of how field staff work. Planograms dictate how a store looks, and handbooks tell employees how to communicate. A monthly calendar mailed from Tennessee includes corporate phone numbers for everything from tracking the status of a bonus check to reporting an open safe. As one Pennsylvania clerk puts it, "There's a department and a process for everything."

Even so, plans deviate.

The opening of a new store in Jersey Shore, Pa., is pressed ahead four weeks, from June to May, because the setter in this area, Mike Koehn, as well as district manager John Anzor are available.

Never mind that local staff isn't yet hired.

To help, Anzor drafts Valerie Hallstrom, a reliable manager he knows from another Dollar General store in nearby Williamsport. "John called me Saturday," Hallstrom says. " 'I need you,' he tells me."

While assistant managers fill in for her in Williamsport, Hallstrom spends her weekend hanging help-wanted signs and calling in an ad for the Sunday paper to recruit helpers for the opening. At 7:45 a.m. Monday, Hallstrom gets to the Jersey Shore store to find a dozen job seekers waiting. Eight hours later, she has hired 20 people to set up a store that isn't her responsibility.

"That's how it is," laughs Hallstrom, who has been with Dollar General for 15 years. "I know how to get these things done."