Paris ? Sophie Guilbaud not only holds a full-time job, she also helps run her son’s nursery and treats herself to regular weekdays of shopping, movies and art shows.

The secret to her balancing act is a remarkable piece of social engineering — France’s 35-hour work week. Introduced under the Socialists but headed for effective abolition by lawmakers today, “les 35 heures” have been a boon for some but, critics argue, a big drain on the economy.

Heated debate about dismantling the working time law has fed into wider political and literary soul-searching in France, on themes ranging from the country’s economic frailty and bureaucratic office culture to whether quality of life should be measured in time or money.

For Guilbaud, a Parisian who works as a loan company manager, that last question is a no-brainer.

“Work is not the only thing in my life,” she said, suggesting she might quit rather than work more hours.

But with unemployment at 10 percent, politicians of all stripes acknowledge that the country’s unique 35-hour law has failed in its original ambition: to force employers to hire massively. What’s more, there are strong signs that it hurt living standards as employers froze salaries to make up for lost labor.

“The intention was to spread work around, but the effect was to spread our salaries around,” Thierry Breton, France’s new finance minister, said last week.

A government-backed bill that effectively restores the previous 39-hour work week is expected to win final approval this week, despite massive public protests earlier this month and denunciations by the now out-of-power Socialists.

Amid soaring unemployment and stagnating wages, the reform is supported by jobseekers and even by factory workers, according to a survey that pollsters CSA published last month — and by 46 percent of the overall population, with 43 percent opposed.

Thousands of people demonstrate March 10 in Bayonne, southwestern France, to defend the 35-hour work week and to push for more jobs and pay talks.

There are other signs that the vision expounded by former Prime Minister Lionel Jospin’s Socialists now rings hollow in some surprisingly left-wing constituencies.

Often touted as the working mother’s godsend, the 35-hour week actually made life harder for poorer women and single parents, according to women’s organization CLEF.

“The women that suffered were the lowest paid, who needed all the overtime they could get to make ends meet,” said CLEF president Monique Halpern. “I think this is one of the reasons that Lionel Jospin lost the elections.”

Clara Gaymard, the globe-trotting head of the French International Investment Agency, contends the 35-hour week has damaged investment in France, mainly because of its negative image in countries like the United States — France’s biggest source of investment.

“The perception was that the French didn’t want to work any more,” she said, whereas French workers remain among the most productive in the world, ahead of Britain, Germany, the United States and Japan, according to the European statistics agency Eurostat.

Gaymard is the wife of former finance minister Herve Gaymard, who resigned last month in a scandal over his lavish publicly funded apartment.

Marc Touati, chief economist at Paris-based Natexis Banques Populaires, conceded the law initially created some jobs and gave large employers an incentive to offer more flexible schedules because there were tax breaks and business was good.

In today’s uncertain economic environment, though, the shorter work week is “destroying jobs because companies wonder whether it’s worth taking people on for just 35 hours a week,” Touati said.

Other governments regulate work hours, but France’s law came under particular scrutiny because it applied to a broad cross-section of workers, rather than to specific professions.

According to a 2003 OECD survey of 25 industrialized countries, only Norwegian and Dutch employees worked less time each year than the French, who worked an average 1,431 hours. German workers put in 1,446 hours, British 1,673 hours, Americans 1,792 hours and Koreans 2,390 hours.

Last year, a parliamentary committee reported that the 35-hour week cost France more than $13 billion a year, casting doubt on a labor ministry study that suggested it had created 350,000 jobs between 1998 and 2002.

Still, many French workers are loath to give up their shorter hours, even for more cash. Some 56 percent of salaried employees oppose the government’s plan, according to the CSA survey, while 36 percent approve.

On March 10, almost a million people took part in strikes and protests over the working time reform — as well as other threats to workers’ benefits and public sector pay.

But Nicolas Sarkozy, who pushed hard for the law to be loosened while serving as finance minister last year and is expected to one day run for president, has no regrets.

“It’s wonderful to see so many people marching to defend the jobs they already have, pushing aside so many others who would also like the chance to have a job,” he said.