What does it take to become a police officer? Mental and physical strength and agility, patience for a lengthy application process, graduation from a police academy -- and a relatively clean police record. 

Indeed, for a job that pays a middling wage, is potentially dangerous and sometimes involves long and strange hours, policing is a demanding career. That's why city police and state troopers tend to be a dedicated, close-knit bunch who do their jobs for the love of serving the public.

From growing towns in the Southwest to the metropolises of the Northeast, there are diverse opportunities in police work. "There are about 18,000 police departments in the United States, but they're not all recruiting all the time," says John Doherty, an assistant professor of criminal justice at Marist College in Poughkeepsie, New York.

Police Work in the 21st Century

Some police chiefs point to recent trends that have changed the job of the patrol officer. Examples include community policing and use of information technology to analyze crime patterns and better allocate law enforcement resources.

But overall, police work is the same as it's always been. "The job of being a police officer hasn't changed greatly," says James Stinchcomb, author of Opportunities in Law Enforcement and Criminal Justice Careers. "You still do a considerable amount of time on patrol; it's very reactive."

Qualifications, Training Rigorous

Many police jobs require a high school diploma and possibly some college study of criminal justice. Applicants will likely be rejected for multiple traffic violations, drug offenses or other issues uncovered by a background check. Then come tests -- physical, medical, intellectual and psychological. In many jurisdictions, a civil-service ranking determines who's likely to be admitted to the academy training program for city or state police.

Competition is substantial. "Most people who apply do not make it," says Stinchcomb. But that initial screening might actually be the hardest part. Indeed, "if you're lucky enough to make it through all those weeding-out processes, then you'll probably make it through the academy," says Doherty.

Police academy programs, which take anywhere from 12 weeks to a year to complete, comprise a variety of coursework, from criminal law to cultural awareness to physical and firearms training.

Some Academies Independent of Police Departments

In some states, including Florida and Michigan, police academies are part of the public higher-education system rather than being linked to individual police departments. "College programs are slowly becoming more portable," says Stinchcomb.

In Michigan, candidates need not affiliate with a particular police department before attending an academy. "We take people off the street, if they pass the tests," says Al Hart, director of the law enforcement program at Northwestern Michigan College in Traverse City. Graduates of Northwestern Michigan's program can apply to police departments of their choice throughout the state.

Room to Move Up or Specialize

For officers who have put in some years on the streets, there's potential mobility in several directions. Veterans can move up the ranks to become a sergeant, lieutenant or even chief, among other positions, or they can specialize in crime lab work or become a detective.

One alternative is to join the state troopers, who do much more than just patrol the highways. State police investigate narcotics and child abuse, reconstruct accidents and even serve as hostage negotiators.

Many of these promotions and specialties require advanced education. A criminal justice school in your region will have more information.