Every so often, your employees' productivity will wane and they will pick up some bad habits. As a leader, you need to find effective ways to change their behavior. Unfortunately, that's easier said than done.

"So often the effort produces an opposite result: rupturing the relationship, diminishing job performance, or causing the person to dig in their heels," Jack Zenger and Joseph Folkman of leadership development consultancy Zenger/Folkman write in Harvard Business Review.

Zenger and Folkman decided to find out how good leaders effect change, so they conducted a study of 2,852 employees and their 559 bosses. The results revealed a set of behaviors that "correlate with an exceptional ability to drive change."

Below, check out the six most important methods leaders should adopt if they want to drive change in their employees' actions.

1. Inspire, but do not nag.

It's worth noting that one of the least effective behaviors was  incessant requests and suggestions. Nagging, the study found, will work against you.

The most effective leadership behavior in driving change, rather, is to inspire your employees. You can inspire your employees by working with them at an individual level to find out what their goals and aspirations are. "Inspiring leaders understand the need for making an emotional connection with colleagues. They want to provoke a sense of desire rather than fear," Zenger and Folkman write. "Another approach in many work situations is to make a compelling, rational connection with the individual in which we explain the logic for the change we want them to make."

2. Pinpoint problems.

The second-most effective behavior is the ability to recognize problems in your company's systems and in your employees so you can help drive positive change. As an example, Zenger and Folkman write that when they were working with one company, employees were being recognized for their "heroic crisis management" for helping get products out on time. When a new manager came on board, she found that that the heroic crisis management was in fact a "symptom of a broken process."

3. Aim for a collective bullseye.

Providing clear goals for the entire team will help you guide employees into positive behavior. "Change initiatives work best when everyone's sight is fixed on the same goal," Zenger and Folkman write. "Therefore, the most productive discussions about any change being proposed are those that start with the strategy that it serves."

4. Kill sacred cows. 

Leaders who challenge the company's standard practices are successful at driving change. The forces that hold teams back from effective change are "old practice and policies--even sacred cows," Zenger and Folkman write. "Leaders who excel at driving change will challenge even the rules that seem carved in stone."

5. Instill trust in your judgment.

Making judgment calls after collecting evidence from both sides of an issue is a big part of leadership and driving change. But you need your employees to trust your judgment. Look at Abraham Lincoln's team of rivals, for example: the president was constantly exposing himself to opposing views and being challenged. Good leaders "recognize that asking others for advice is evidence of their confidence and strength, not a sign of weakness," the authors say. "Because of their ability to build trust in the decisions they make, their ability to change the organization skyrockets. If others do not trust your judgment it will be difficult to get them to make the changes you want them to make."

6. Be courageous.

This may sound like something out of a self-help book, but courage and successful leadership go hand in hand. Everything you will do as a leader requires courage. "Indeed, every initiative you begin as a leader, every new hire you make, every change in process you implement, every new product idea you pursue, every reorganization you implement, every speech you deliver, every conversation in which you give difficult feedback to a colleague, and every investment in a new piece of equipment requires courage," Zenger and Folkman write.