“Be where you need to be.” I first came across this concept when I started working for Gagen MacDonald a few months ago. Be at your client, in the office, at home, in the park – wherever you are needed, wherever you are most productive. What’s necessary to make this work? Responsibility, accountability, self-discipline. But most importantly: Trust.

Netflix, a company known for its performance-driven culture, takes employee freedom a step further: For nearly a decade now, Netflix hasn’t had any vacation policy or tracking. As former Chief Talent Officer Patty McCord put it, “There is also no clothing policy at Netflix, but no one has come to work naked lately.” She has a point.

The honor based system is sparking interest across industries – Best Buy, Morningstar, Zynga, HubSpot and a growing number of smaller companies have bid farewell to traditional vacation restrictions and are adopting more flexible time-off policies.

Still, the trend has yet to take off – according to a study of the Society for Human Resource Management, only 1% of US companies provided their employees with unlimited PTO (paid time off) in 2012. And, it is mostly limited to the US, the only developed country in the world without legally required paid vacation. Innovation in the field of employee freedom seems to not only be a question of corporate philosophy, but also of society and culture.

Having grown up and spent the first decade of my work life in Germany, these ideas struck me as extremely trusting, and admittedly, a little wild. Back home, people typically have between 5 and 6 weeks of paid annual vacation, (by law, the minimum in the European Union is 20 days) plus up to 11 paid public holidays – often more time than people can actually take in a year. And, still – everyone knows exactly how much time they have left, down to 15-minute increments. In this context, policies, time sheets and half-day application forms make sense, and the idea of unlimited PTO naturally causes discomfort and skepticism. It seems scary to think that there could be only one rule instead of all this: The work needs to get done, and clients or colleagues can’t be left in a bind.

A recent article in Germany’s hip business magazine brand eins introduces the concept of unlimited leave policies as “seemingly foolish,” but later points out that its results are different from what one would expect: Increased productivity. Motivation in the workplace. Employees who feel trusted, valued and in control. An attractive proposition for recruiting talent.

Clearly, flexible PTO concepts are not practical for all types of business. And, what about the risk of extended round-the-world trips, or 5-week flus? Zynga’s former Chief People Officer Colleen McCreary said: “We hire great people who are all invested in growing the company so we trust them to make good decisions about their time.” Gagen shares a similar view, telling employees: “We believe our trust will result in better work for our clients, and a better work life for our employees.”

Having a company’s top leaders express this kind of confidence to their people is a cultural statement that will go a long way. Research and experience show that in most cases, the trust is returned. Off the clock.