William Bratton recently got his second bite of the Big Apple. Rudy Giuliani appointed him chief of police for New York City in January 1994, and 20 years later, Bratton returned to the post under newly elected Mayor Bill de Blasio.

On June 28, I taught a case about Bratton's first time as New York's top cop to 39 Babson College M.B.A. students in my Strategy and the CEO class. And I realized that the methods he used to boost the performance of New York's police department could be applied to any organization--especially a startup.

Bratton took over a deeply demoralized department in January 1994, and within 24 months, he had made a significant positive difference. New York's burglary and homicide statistics had plummeted so much that New York accounted for 61 percent of the U.S.'s reduction in crime in 1995. Moreover, police department morale had soared, and so had the perception of the department in the eyes of New York residents.

Bratton used five change levers to get these results. And if you are running a startup, you ought to get some valuable takeaways from understanding how Bratton did that.

1. Change the mission.

Before Bratton arrived, the police department's real mission was to put as many people as possible into the police department. Simply put, it was a classic bureaucracy where the measure of executive power was the number of people in that executive's department.

Bratton changed that mission--making every person accountable for reducing the amount of crime in the city. This simple conceptual change--from measuring resources to counting crime reduction--led to other changes.

2. Change the people.

Bratton's experience before taking over as New York police commissioner made him very skeptical of precinct commanders who stayed in their offices and tried to avoid doing any extra work--like going out into the streets to help support their officers.

Bratton met with the precinct commanders and other top executives in the department and tried to find one who he thought could embrace his new mission. He found that about 25 percent of them could do what he needed--he fired the other 75 percent.

3. Change the strategy.

Before Bratton took over, New York was trying out the concept of neighborhood policing--in which a police officer would be assigned to particular neighborhoods and try to get to know the people better to nip crime in the bud. But neighborhood policing wasn't implemented very well, given that junior officers were assigned to those beats, and they lacked the experience to make the best decisions.

When Bratton took over, he revamped the department's strategy. He took a survey of the department and assembled teams of officers who went to work developing solutions to the seven biggest problems that the survey identified.

The result was seven new strategies, including getting drugs off the streets and wiping out corruption in the department. This so-called reengineering process drew eye rolls from the rank and file who did not think this was an important part of their job, but it also got them to buy into the strategies.

4. Change the structure.

When Bratton arrived at the NYPD, it was hard to figure out who was responsible for what. So he created 76 clearly defined precincts--distinct regions of the city--and assigned commanders whom he held accountable for reducing crime statistics within their precincts.

5. Change the scorecard.

Bratton defined success at the NYPD in a new way. Instead of counting the number of people in a department, he measured the change in crime counts of different kinds within each precinct. Every two weeks, the precinct commanders would meet with one of Bratton's staff members and explain how they would make those crimes go down.

If they did not achieve the results they promised, those commanders would return to the so-called CompStat meetings more frequently until their precincts got better results.

Can Bratton's example help your startup? I think the lesson is pretty clear. If you are not getting the results you need, consider whether you need to change your startup's mission.

And to make sure your startup realizes that mission, consider replacing people, changing strategy, altering your organization structure, and building systems that measure and reward a new definition of success.