Just before New Year’s Eve, Chicago Police confirmed 2012’s 500th homicide in the city, surpassing that landmark for the first time since 2008 and breaking a three-year downward trend. The number is, as Police Superintendent Garry McCarthy put it in a word, tragic. The human toll of such violence ripples out immeasurably.

What should urbanists, architects, and planners take from crime data? Statistically the country’s cities are safer than they have been in at least decades, if not ever. A Brookings Institution analysis of FBI and Census data found that between 1990 and 2008, both violent and property crime declined significantly in the country’s 100 largest metro areas, with cities showing the largest decreases. But that does not tell the entire story.

Not all cities are the same. New York, which has three times the population of Chicago, reported only 414 homicides last year, the lowest since the city started recording such data in 1963. And while the Chicago-Naperville-Joliet metro area showed the largest decline in violent crime rates in the country between 1990 and 2008, with city violent crime falling 80 percent, 2012’s murder count should give everyone pause.

The absolute crime rate remains much higher in cities than suburbs, but cities are closing that gap. Indeed, 25 percent of U.S. murders now take place in suburbs, up from 20.7 percent in 2001. Is crime moving to the suburbs?

First of all, we should be careful not to draw artificial distinctions. Some suburbs are transit-oriented and dense, while technically urban city fringes exhibit conventionally suburban characteristics. Older, high-density suburbs logged the largest declines in crime rates between 1990 and 2008, compared with other suburban and exurban communities. But violent crime in Chicago’s suburbs actually fell slightly faster than it did in the city during the same time period.

We tend to think of suburbia as uniquely isolating—sprawl forces residents to ferry themselves from place to place inside their cars—while urban centers appear cosmopolitan and social. A recent analysis by local news site DNAinfo Chicago, however, mapped all 509 of Chicago’s 2012 murder victims and found a staggering proportion of them (nearly 4 out of 5) were killed less than half a mile from home. Indeed, because of gang boundaries, some young people in Chicago have never even been to Lake Michigan.

Gated communities in the suburbs can lead to racial stereotyping and fear. Of course, statistical associations between race and crime drop precipitously as suburban communities diversify. Instead of endorsing prejudices against urban living held by some outside city limits, we should recognize that it is persistent, concentrated poverty that breeds crime—whether in the city or the suburbs—not some inherent failure of an area’s residents.

So beyond the simplistic distinction between city and suburb, what lessons do recent crime statistics have for urbanists? Crime is contagious, and socioeconomic segregation drags everyone down. The poverty and foreclosure crises have hit Chicago’s suburbs hard in recent years, which should drive home the point that these are not uniquely urban afflictions. Clearly this is an extremely complex issue, but it is not intractable—and the design community can be part of the solution.