Every effective leader understands the importance of communicating with employees. But because most leaders concentrate on organization-wide communication like town hall meetings, email announcements, and blog posts, they fail to take advantage of a crucial approach for engaging employees.

That approach? Informal small-group or one-on-one conversations.

"Town-hall meetings and other venues give employees a chance to hear from their leader, but they keep the leader at arm's length," says Colin Lange, North America executive director for brand engagement at  Landor, the brand consulting and design firm. "And the encounter is largely one-way: The leader talks and employees listen."

In my experience, leaders concentrate on those formal venues because they think it's the best use of their time. As one leader told me, "I'm so busy that I need to concentrate only on high-impact activities."

But Lange explains that informal communication encounters--walking around, having 10-minute chats, asking a few people to have coffee, eating lunch in the cafeteria--are high-impact activities that improve employee engagement.

To understand why, it's helpful to recall the work of Edgar Schein, former professor at the MIT Sloan School of Management, whose book Organizational Culture and Leadership is recognized as essential on the topic. Schein explains that culture is experienced within an organization in three key ways: in observable artifacts, espoused values, and basic underlying assumptions.

We'll focus on "observable artifacts," which Schein describes as an organization's attitudes, behaviors, and beliefs--what it considers important and meaningful.

As Lange explains, when a leader has an informal interaction with an employee, that leader is sending a strong signal about culture--he/she is creating an "observable artifact."

"By stopping and talking to an individual employee, you demonstrate that you are interested in what that person is working on and has to say," says Lange.

Plus, those conversations show that you're not on a pedestal or sequestered in the executive suite; you're a regular human being who relates to other human beings. That connection builds trust.

And every informal encounter has "a ripple effect in the organization," says Lange. "Other employees notice that leaders are interacting in a personal, caring way."

All of that is important, but the value of those interactions doesn't stop there. An informal conversation is not only meaningful to the employee, it's a unique opportunity for you as a leader to gain perspectives that will help you be more successful.

Although you may feel like you spend every waking moment in meetings, you're only exposed to a narrow group of people within the organization: usually other leaders, people who head functions and initiative owners. And many of those people are trying to impress you, so they carefully craft their messages to put a positive spin on things.

But by reaching out to all levels of employees, you have the opportunity to get fresh viewpoints on what's happening throughout the organization. People are more likely to be candid in one-on-one or small-group conversations, especially when your focus is on observing what they do and listening to them.

Lange tells the story of a company headquartered in Chicago that appointed a new CEO. A few weeks after the CEO came on board, she paid a visit to the company's second largest location in the New York City area.

"The CEO walked into the office and went immediately to the large conference room, where she stayed all day," he says. "She had a series of meetings at which department heads presented their plans and progress. At lunchtime, food was brought in and the meetings continued throughout the afternoon."

The CEO probably thought the day was productive, but she missed an important opportunity, says Lange. "She would have demonstrated her openness and interest in listening if she had simply walked around the office and chatted with people. Even better, she could have visited the cafeteria for 30 minutes and eaten her salad while getting to know some team members.

"And, by asking the right questions, the CEO could have learned some things about the company that she didn't hear by talking only to leaders," Lange says.