For much of the last decade, the retailing behemoth Wal-Mart Stores has been associated with stingy health care as much as low prices.

Across the country, politicians and labor groups derided the company’s health plans for their high expense and bare-bones coverage. Two states, California and Maryland, even passed laws demanding, in effect, that the company spend more on employee health benefits.

“We want this giant to behave itself,” one Maryland legislator, Anne Healey, said at the time.

The giant, it turns out, was listening. All the criticism was hurting its reputation and its ability to expand. So now, after spending two years seeking advice from everyone from Bill Clinton to executives at Starbucks, Wal-Mart is overhauling its health plans.