One of the questions I most often hear from readers seeking work/life balance is “How do I get my manager to give me flexibility?”

Sometimes it comes from a mother who is struggling to take care of an infant and keep her job. Other times, the question comes from a male boomer who can’t stand the commute and wants to work from home a few mornings. Surprisingly, it even may come from someone whose company has a policy that embraces flexible work arrangements.

Typically, it’s a middle manager who stands in the way.

“Manager resistance can be one of the biggest barriers to workplace flexibility,” said Kyra Cavanaugh, president of Lifemeetswork, a flexible workplace consultancy firm.

Just last week, a young associate at a Miami law firm told me she asked her boss if she could work from home occasionally when she doesn’t have to appear in court. “He didn’t even take a breath before he blurted out no,” she complained.

Taking a manager from no to yes can be done, gradually or quickly, with the right approach. And when on board, managers who supervise staff members who work flexibly find their teams usually perform better, too. “Rather than it being a herculean task that requires extra hours to manage, it’s really about being a good manager,” Cavanaugh says.

The definition of working flexibly has expanded in recent years, encompassing everything from shifting start and finish times to working four-day work weeks to working some or all of the time from home, or a variety of other arrangements.

The most common manager objections to flexible working revolves around trust and control: How do I know you’re working if I can’t see you? What if I need you and you aren’t available?

Cavanaugh says the employee has to go in with a plan that includes more communication. “Have a conversation about expectations, deadlines, milestones, work hours, how often you will evaluate the arrangement.”

Another big manager concern is productivity: If I give you flexibility, what’s the impact on productivity and client service?

Beyond face time, how does your manager measure productivity? If he doesn’t, devise short and long term metrics to make your case.

After becoming a mother of two, Risa Steinman wanted to work a part-time schedule as a sales representative at a call center for DentalPlans.com in Plantation. Her manager, Margaret Keen, vice president of sales, was reluctant. It had never been done. “We have sales goals to make and I was not sure she would be able to meet them,” Keen said.

Steinman enthusiastically argued that she was sure she could meet the goals, even on a reduced schedule. Keen agreed to give the arrangement a try. They set a quota based on the number of hours Steinman would work. Within the first 30 days, she exceeded it and has continued to prove herself for the last two years. “I come in focused and I often sell as much as full-time sales people,” Steinman said.

Seeing the arrangement can work, Keen has allowed nine others part-time schedules that accommodate employees’ work/life needs. Still, as a manager, Keen says the business needs to remain her priority. “We’re a call center so I have to plan ahead and staff accordingly.”

Cavanaugh says managers often can be won over if they are made to see the advantages of flex, particularly if it’s higher productivity. “Every manager wants a high-performing employee. It makes them look good.”