A DECADE ago, when Prince George’s County was challenging the District for the dubious title of the metropolitan area’s murder capital, it seemed that practically anyone could get shot. One sweltering summer day, the county’s chief prosecutor and a well-known local politician were standing in line for ice cream when a drive-by shooter fired a pellet gun, apparently at random, hitting them both.

Neither was seriously injured, and the politician, Rushern L. Baker III, is now the county executive. By some combination of good luck, smart policing and the shrewd deployment of resources, he is in the enviable position of presiding over the county as its crime rate plummets.

Last year 57 people were murdered in Prince George’s, a drop of about 65 percent from the 161 killed in 2005. This occurred as the county’s population grew by more than 40,000, to 880,000. Carjacking, once an epidemic, has fallen by almost 60 percent in the past three years, according to the Prince George’s County Police Department. Violent crimes such as assaults and robberies are way down, as are property crimes, including burglary and car theft. Formerly crime-ridden places inside the Beltway — Suitland, Seat Pleasant and Langley Park — feel safer to many residents.

The credit goes to several initiatives, including a state law allowing police to deal more efficiently with minor offenses such as public drunkenness and scuffles, a beefed-up prosecutor’s office, clever use of social media for crime (and punishment) reporting, and a program spearheaded by Mr. Baker that focuses on sprucing up neighborhoods.

Perhaps the key factor is more officers on the ground. The number of uniformed officers in the county, now around 1,700, has grown about 30 percent since 2005. Five years ago, police officials complained that too few officers and patrol cars made it impossible to project their presence in tough neighborhoods. That’s changed. Another 100 officers are expected to be added to the force this year, and, if promising economic trends continue, 200 or more may be added in the following four years.

That may sound like a dizzying increase, but consider what’s coming. MGM Resorts is planning to build a $1 billion casino at National Harbor. Tanger Outlets has opened a huge mall, also at National Harbor. The county is to welcome a major regional hospital and may become home to the FBI’s new headquarters, with 11,000 employees. Developers are planning what may become a mini-city of 10,000 houses plus offices and shops at Westphalia, near the Beltway at Pennsylvania Avenue.

The overall picture is of a county on the move. That’s a dramatic image shift for Prince George’s, for years a regional laggard becuse of crime, failing schools, sluggish commercial development and corrupt governance. Mr. Baker, with a major assist from the police, is rebranding the county at breakneck pace. The falling crime rate, critical to that rebranding, will help open the door to better standards of living.