At the T3 advertising firm in Austin, employees have a saying: It takes an agency to raise a child.

The $261 million company, whose clients include Marriott International, Microsoft and J.C. Penney, lets a new parent bring the baby to work — every day — until the child is old enough to crawl.

Almost 50 babies have spent their infancy in the office beside their mothers or fathers, who generally tote in baby swings and playpens to set up makeshift nurseries, even bringing infants to meetings in BabyBjorn strap-on carriers.

It's not as unusual as it may sound. More than 80 firms now allow babies in the workplace, according to Parenting in the Workplace Institute in Framingham, Mass., and that number is likely to be low. It's an extreme example of a growing trend by employers to help balance work and life.

The number of companies allowing children at work on an occasional basis climbed to 29 percent last year from 22 percent in 2006, according to the Society for Human Resource Management.

Productivity specialists are raising eyebrows at the practice, saying it may amount to favoritism for parents and rankle co-workers who don't want to put up with a baby gurgling — or worse — in the next cubicle.

"Those without children often come to resent the perception of coddled working parents," says Tory Johnson, CEO of Women For Hire, a New York-based professional recruitment services firm.

Some parents who've brought babies to work admit it doesn't go without a hitch, and some co-workers raise concerns about the practice with management.

Francine Gemperle, 33, a designer and researcher in Pittsburgh, brought her son Milo to work every day after a six-week maternity leave.

"He did not sleep all the time and had to be walked around," she says. "This is not for everybody. Not every baby can do it. You couldn't do it with a colicky baby."

But the practice is continuing, and this is far different from on-site day care centers. Employers who let workers bring babies every day include retail companies, insurance firms, law offices and credit unions, and most parents keep their children at their desks.

At T3, new parents are offered private offices, and the babies are allowed to come to work daily until they are mobile, usually around 9 months old.

The perk isn't just for working mothers: 10 fathers at T3 have participated. Toys that one parent uses are often passed to other new moms and dads coming back to work with their babies, spokeswoman Courtney Layton says.

"It's been fun," she says. "You can't be in a bad mood when there is a baby there."

Allie Hewlett, 33, a benefits administrator at T3, brings her 7-month-old daughter, Scout, to the office most days. Bringing Scout in, she says, helped alleviate the anguish over leaving her in day care, which she plans to do when Scout becomes more mobile.

Hewlett had been sharing an office with co-workers but moved to a private office now that Scout accompanies her to the job.

Along with her briefcase, Hewlett brought a Pack 'n Play, an Exersaucer, a bouncy swing and other baby paraphernalia that she set up beside her desk.

"Scout is so well-adjusted, and people come over all the time to play with her. They jump at the chance to watch Scout for 20 minutes if I have a phone call," she says.

DEEPENED LOYALTY

Hewlett handles employee orientation and greets new hires by showing up with Scout in a carrier strapped to her chest. Being able to bring her baby to work, she says, has deepened her company loyalty.

"I feel extremely indebted to have this opportunity," she says. "I can't even imagine working anywhere else."

The trend, driven by a growing number of women in the workforce and a desire by companies to become more family-friendly, is also eliciting criticism.

Bringing children to the office, whether once in a while or every day, also raises legal concerns for employers, creates a distraction that undermines productivity and may not be the best environment for a baby to get interaction and stimulation.

"There are concerns that employees may feel unable to complain if their managers bring in babies," says Robin Ryan, a career coach and author of "Soaring on Your Strengths." "Babies may cause such a distraction that other employees who want to spend time with the infant find it hard to focus on their own work. Still others say that bringing babies to work can make new parents look less devoted and focused on their jobs."

Ryan also notes that most people will tolerate a one-time event. "But the reality is the parent can't pay 100 percent attention to the job, and the child is often distracting to other employees."

She says a doctor who brought her infant to a hospital in a sling around her neck was then unsure what to do when she needed to do a medical procedure, because the baby was literally in the way.

NOT A GOOD IDEA

Some employees who've worked with these parents say it's not a good idea. Mike Prencipe, 48, managing partner of HR Staffing Solutions in Springfield, Va., had a colleague who brought an infant to work three days a week.

"You'd have a client calling and you had a screaming baby in the background," Prencipe says. "First off, it's a distraction. Everyone wants to ooh and aah over the baby. And it's a distraction to the parent, because they have to tend to the baby first, as well they should. I don't think it's a good idea."

At Maya Design, a consulting firm and technology research lab in Pittsburgh, new parents can bring babies to the office until they are about 6 months old. There are stipulations: no infants with a fever higher than 100 degrees, and parents must sign a liability waiver.

When word got out that babies would be allowed at work, some employees raised concerns with management. Gemperle, who works at Maya and brought son Milo to the office, says she breast-fed him in a special room. She borrowed a compact bassinet that she kept next to her desk, along with a supply of blankets, diapers and a changing pad — although she always changed Milo in the restroom on a long counter.

Milo, now 2, went to work with his mother for six weeks before he began the transition to day care.

"I would wear him in a BabyBjorn (carrier) in meetings and just stand and bounce him around. At 12 weeks, he would make noise and flap his arms when co-workers would walk by," Gemperle says.

To avoid problems, she sent an e-mail to co-workers within 15 to 20 feet of her cubicle and warned they would sometimes hear a baby going "blah blah or gurgling."

To help avoid pitfalls, many companies have drafted policies that cover everything from whether sick children are allowed and how to handle complaints.

"With no guidelines or structure, it didn't work for some companies. Babies cried for long periods," says Carla Moquin at Parenting in the Workplace Institute. "There were no clear expectations from the beginning."

Steve Abernethy, CEO of San Francisco-based SquareTrade, a provider of warranties for consumer electronics, says he couldn't imagine babies on the job.

"It would be a very difficult distraction. It wouldn't work. We have a completely open floor plan," Abernethy says. "We have plenty of people with kids, but ... I think it would be very difficult for the parent and people around them to be productive."

Many companies balk at the concept of babies at work full time. At Ernst & Young accounting firm, parents can get subsidized, backup child care in their homes.

"It's for the good of the child," says Sandra Turner, director of the company's employee assistance program. "It's better for them and for the parent."

Employers who allow babies say it's a way to retain valued workers.

"Four women got pregnant within a couple of months of each other, and they were in fairly senior roles," says Gay Gaddis, president and founder of T3, a business with 250 employees. "I was panicking. I thought, 'What if they don't come back?' Now the babies are here, in internal meetings and being fed on meeting tables. Little babies are learning to type on the computer before they leave. It does a lot for morale."

She admits there were hurdles. "My attorney was, like, 'You're not a licensed day care,' " Gaddis says.

'OUR ATTORNEYS SHUDDERED'

When the first baby was allowed at Maya, spokeswoman Terry Pronko says, an e-mail was sent to alert all employees, and the new parent had to sign a release form. "Our attorneys shuddered," Pronko says.

Employees who bring kids to work must use their own baby equipment and log the hours worked. Workers aren't paid for the time spent caring for their infant on the job.

During the first 18 months of Maya's baby-friendly policy, the company has had four infants in the office, a modern building with an open layout. In the next nine months, the company is expecting four more.

Maya employee Maryl Curran Widdows, 35, a senior program manager, took her infant daughter, Elinor, to client meetings.

"I did it when it was appropriate and checked first," Widdows says. "I'd wear her in a carrier, and stand and make her happy. She was quiet and didn't interrupt."

Her husband also used to work at Maya, and whenever she was busy, she would roll Elinor's bassinet across the office so he could watch her.

She had feared Elinor would be disruptive because of the open design but says it worked well. Elinor, now 20 months, went to the office almost daily for three months. During breaks from work, Widdows would take her daughter in a stroller to the nearby park.

'ALLOWED AND ENCOURAGED'

Dallas-based CDG, a human resources software consulting company with 20 workers, allows babies at work until they are about 6 months old.

"It's allowed and encouraged," says CEO Deborah Driskill. "If there is a meeting, another employee will watch the baby or it will be brought to the meeting. It's good for morale."

One consultant brought her baby to work for seven months before the child died unexpectedly (not in the office) from an undiagnosed heart condition. "We gave her the gift of having that time with her baby," Driskill says.

What about the impact on the child? Karissa Thacker, a management psychologist in New York, says, "Space is important, as is having projects to occupy children. Without appropriate attention and care to the environment, the child is more likely to act bad."

At George Watts & Son, a retailer in Milwaukee, the CEO's office has been set up with a crib, rocking chair and a playpen.

"Being in a retail environment is fabulous for the babies," says CEO Sue Thome-John, who brought her 2-year-old son to work until he was 9 months.

"There are lights, beautiful objects and always being around people. My desk is on the retail floor, and I'd put him in an infant chair, and he could just watch the customers."