Any parent with two or more children picks up one lesson in a hurry, Ann Crittenden says: Although you might set the same rules, your children will have different interests and skills, different likes and dislikes. It would be absurd and frustrating for everyone involved if you treated them exactly the same.

Yet many employers take exactly that step with a wide range of employees, applying one-size-fits-all management techniques to an irregular world.

“Bring out the most of every employee,” says Crittenden, author of “If You’ve Raised Kids, You Can Manage Anything” (Gotham Books). “Don’t ask them to be the same.”

Crittenden, a former economics reporter for the New York Times and the parent of a college student, wrote her book after having interviews with nearly 100 people. She learned that books about parenting often contain the same basic advice as those for managers, especially on such topics as negotiating.

“You can read a $10.95 child-rearing book and get the same things you hear out of Harvard,” said Crittenden, the author of three other books, including 2001’s “The Price of Motherhood.”

Besides learning to negotiate, parents have three other skills that are particularly helpful to them in the workplace, Crittenden said:

— Multitasking. “You learn how to focus with incredible distractions.”

— Mentoring. “If you’re a decent parent, you know you don’t get anywhere telling people they’re no good.”

Crittenden said good bosses counsel employees, but aren’t so overbearing that they won’t let workers take well-researched and well-thought-out risks — even if they make mistakes. “That’s the only way they learn. Just like kids.”

Being supportive is also crucial in both cases. Sometimes you do need to criticize, but the worker needs to get something constructive out of it. “Let them know you’re behind them.”

— Having a sense of perspective. “If something goes wrong at work, they know it’s not the end of the world.”

In the book, Crittenden points to one parenting technique that can help bosses and workers get what they want — as long as they’re not obvious about it.

“If you want a child to eat a vegetable, for example, you offer alternatives,” Crittenden writes. “You don’t say, ‘Eat your spinach!’ like the mom in the old Thurber cartoon. You say, ‘Honey, would you rather eat spinach, carrots or squash?’ The child gets to pick, buys into his selection and thinks eating a vegetable was his idea all along.

“By the same token, never ask open-ended questions like ‘What would you like for breakfast?’ opening the door to answers like ‘cake and ice cream.’ Just inquire, ‘Do you want your milk in a cup or a mug.’ ”

Crittenden explains in the book that the Queen Isabella who sponsored Christopher Columbus’ voyage used that technique when she wanted the pope to appoint her servant as archbishop. She offered a list of three candidates: the servant and two obvious incompetents.

She also writes about how a parental strategy can solve a sensitive workplace problem without resorting to a confrontation with the offending colleague.

“A friend of mine tried this out-of-the-box technique on a foul-mouthed co-worker who was constantly losing his temper and erupting with the F word,” Crittenden writes. “Every time he did it, she’d go, ‘Pluck, pluck, pluck! Listen! There must be a big chicken in here!’

“She’d learned the trick by pretending that she was a bird, flapping her wings and dancing, to amuse and divert her irritable 3-year-old. Sure enough, that ill-tempered oaf in her office go so embarrassed by her chicken routine that he cut out the obscenities.”

In the interview, Crittenden said a good manager is like a “benevolent parent.”

“It’s just fallacious to think home and office are two separate spheres,” she said. “You’ve got to be firm at home, as well as gentle. You’ve got to be gentle at the office, as well as firm.”

And if managers get discouraged, they ought to remember that their challenges just might not be as tough as parenting. “You can’t fire your kids,” Crittenden said. “So in that sense, it is more difficult.”