Tales of male staff members being discouraged from long leave are still not uncommon, although it is not fashionable to say so. Mr. Boklund said his office “was not happy” about his extended absence.

Bodil Sonesson Gallon, head of sales at Axis Communications, an IT company that specializes in video surveillance, admits that parental leave can be disruptive — for careers and companies. She laments that with preschools starting at 12 months and little alternative child care, there is huge pressure for parents to take at least a year off.

Small businesses find it particularly tricky to juggle absences, said Sofia Bergstrom, social insurance expert at the Confederation of Swedish Enterprise, which represents 60,000 companies. Worse than parental leave, she says, is the 120-day annual allowance for parents to tend to sick children, which is impossible to plan and which is suspected of being widely abused.

“The key issue for business is planning ahead,” said Ms. Bergstrom.

But in a sign that the broader cultural shift has acquired a dynamic of its own, a survey by Ms. Haas and Philip Hwang, a psychology professor at Goteborg University, shows that 41 percent of companies reported in 2006 that they had made a formal decision to encourage fathers to take parental leave, up from only 2 percent in 1993.

Some managers try to make the most of the short-term openings to test potential recruits. Others say planning longer absences is easier and encourage fathers to take six months rather than three. A system of flexible working hours has evolved. Even senior employees may leave at 4:30 p.m. to collect children from school, but are expected to log on at home at night. A growing number of employers top up the salary replacement the state pays parents to 90 percent of their salary for several months.

For many companies, a family-friendly work pattern has simply become a new way of attracting talent.

“Graduates used to look for big paychecks. Now they want work-life balance,” said Goran Henriksson, head of human resources at the cellphone giant Ericsson in Sweden, where last year 28 percent of female employees took leave, and 24 percent of male staff did. “We have to adapt.”