The Obama administration said the law is helping millions of workers cope with family hardships with little disruption to employers, putting to rest fears raised two decades ago that the law would drive companies out of business and lead to rampant fraud and abuse.
"Workers should not have to choose between the job they need and the family members they love and who need their care," acting Labor Secretary Seth Harris said at an agency ceremony marking the anniversary.
Harris was joined by former President Bill Clinton, who signed the measure into law in 1993 and said he has received more thanks from people for the family leave act than for any other law passed during his presidency.
"People desperately want to have successful families, to be good parents and to have a job and succeed at it," Clinton said. "If you take one away to get the other, the country pays a grievous price and every life is diminished."
Since the law took effect, workers have taken leave more than 100 million times. About 57 percent went on leave for an illness. An additional 22 percent took leave for pregnancy or child care and 19 percent cared for a sick relative.
The law allows eligible workers up to 12 weeks of unpaid leave without fear of losing their jobs. Most leaves are relatively short, with 40 percent of workers reporting they were away from work for 10 days or less, the survey said. But nearly half of workers who said they needed leave but did not take it said they could not afford unpaid leave.
At the same time, 85 percent of work sites covered by the law reported that compliance was "somewhat easy," very easy," or had "no noticeable effect," the report said.
Nancy Hammer, spokeswoman for the Society for Human Resource Management, said employers support the spirit and the intent of the law, but "the difficulty comes in the regulatory scheme and how difficult it is to administer in the workplace."
She said employers ask more questions about complying with the family leave act than anything else and often have a hard time with workers taking intermittent sick leave and determining what is a serious illness under the law.
Nearly half the workforce is not covered under the law, which applies only to companies with 50 or more employees and those working at least 24 hours per week.
Some worker advocacy groups, like the National Partnership for Women & Families, want the law expanded to include more workers at smaller companies. They also want Congress to consider a national paid family and medical leave insurance program.
In a statement, President Barack Obama called the law "a groundbreaking step forward for America's workers and families" but said "there is still more work to do" for those left uncovered.
"So as we mark this anniversary, let us also recommit ourselves to the values that inspired the law and redouble our efforts on behalf of fairer workplaces and healthier, more secure families," Obama said.
The Labor Department took a smaller step in expanding the law Tuesday, approving new rules that allow military families to take leave to care for service members who are injured or called to active duty on short notice. The rules also extend the law to airline personnel and flight crews.
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