This group found a simple way to get messages from homeless people to their families.

A novel way to help young men growing up in communities in which concentrated poverty, violence and unemployment are well-documented barriers to health and longevity: male youth of color are trained to be the emergency response team to help stabilize street victims before doctors or nurses begin procedures.

Palm Beach County, Florida has many of the same social problems that Philadelphia has, including “gangs, drugs, and poverty.” However, their school system has managed to keep students safe by employing “safe-school case managers” who build relationships with students, and they offer a youth court that is a system run by students who peer-review cases of unrest. The initiatives in this county has prevented school violence from happening without metal detectors and just two police officers.

CitiStat has show great success in cities like Baltimore, where it has improved city services' efficiency (removing snow, fixing potholes, etc.). Many cities use Stat programs, but Baltimore has been a particular case of success. Looking at how it implemented its CitiStat program holds lessons for other cities.

In the past, Los Angeles was a dangerous city fraught with gang wars. Lately, though, LA has become a safer city due to six changes enforced by the police cracking down on public violence and gangs.

By partnering with cities across America, the 100,000 Homes campaign is going directly to the streets to end homelessness - and it’s working. With roughly 700,000 people in the United States experiencing homelessness, this organization seeks to address that using a tiered system that considers individual health needs as well.

The use of a gun in a violent crime can carry a penalty of 30 years or more in prison. High Point, NC, has been using call-ins for 16 years - a carrot-and-stick approach aimed at reducing violent crime and drugs in the city.

In India, videos made about the many social problems are secretly broadcasted in different villages to make people aware of the real problem and also aware of what they can do to fix it. Video Volunteers, an organization that coordinates these video productions, catalyzes community change through transparency and accountability.

Americans often want to connect to a cause beyond writing a check. Crowdsourcing is creating new forms of philanthropy globally, giving donors more choice and a stronger connection to the projects they fund.

Harassment on the internet is more accepted but just as harmful as it is in person. RiotGames, a game publisher, decreased abuse by enabling its gaming members to decide and enforce community norms.

Colombia has attempted to decrease murder and homicide rates by setting up curfews for teenagers, forcing bars to close earlier in the evening, and creating gun laws to prevent the carrying of weapons. As a result of this epidemiological, data-driven approach, along with other governmental factors, the homicide rate has decreased significantly in most of the cities in which it was implemented.