There is no "silver bullet" to reduce armed violence, a multi-faceted, complex phenomenon with a long list of drivers, risk factors and causal connections. Moreover, the local manifestation of armed violence often reflects unique factors and peculiarities found in a given community, country or culture, but not elsewhere.

As once noted about politics, all violence is also local; as such, there are many different interpretations of the best ways to confront this global epidemic with local 'symptoms'. A proven approach for one circumstance may fail miserably a few hundred kilometers away if the transposition is attempted in a 'cookie cutter' fashion, without respecting local knowledge, dynamics and institutions.

That said, there are problems (and thus solutions) that can be generalized, if not globally, for a given geographical scope. Often times within a country or sub-region, the "tools," "actors," "institutions" and "impacts" concerning armed violence are, in fact, quite similar. While there are no universal patterns, there certainly are trends and levels of magnitude that should be respected.

One of these is the preponderance of small arms use in the global armed violence 'epidemic' -- over a half million killed annually. While levels of armed violence vary widely among world regions, firearms (mostly handguns) are a major part of the story everywhere. Even in regions where armed violence is a relatively small problem (such as Western Europe), guns are often a considerable proportion of said small problem. In the sub-regions of the world where armed violence is ravishing communities and killing scores of people, whether in conflict or countries 'at peace', firearms are always protagonists. Six of the seven countries in the world with most recorded violent deaths between 2004 and 2009 were from Latin America and the Caribbean -- El Salvador, Jamaica, Honduras, Colombia, Venezuela and Guatemala (the exception is Iraq). All six have a rate over 43 murders per 100,000 -- El Salvador with 62. The World Health Organization considers any level over 10 per 100,000 "epidemic" -- the average annual global violent death rate in the period was 7.9; in Europe less than 3 per 100,000.

In the Americas, 66 percent of homicides occur with firearms, and the availability of illegal guns seems to be driving rising homicide rates in Central America and the Caribbean -- the only sub-regions in the world recently experiencing increases. All countries in which 70 percent or more of homicides are committed with firearms have rates over 20 per 100,000 -- and all are in the Americas. Moreover, firearms are overwhelmingly involved in violence at large -- not only homicides nor only vis-à-vis other types of weapons within the 'armed violence' rubric.

Closer to home for us, an estimated 70 percent of Brazil's globe-topping 50,000 annual homicides are committed with firearms. In the specific case of São Paulo, according to our recent research, 61 percent of all homicides committed in the city in 2012 and first half of 2013 were committed with a gun.

This was actually a significant decrease from a decade earlier, which may be explained by less accessibility to weapons due to gun control measures: between 2000 and 2010, over 200,000 illegal guns were seized by the police -- while more than 130,000 firearms were voluntarily surrendered by citizens in buy-back campaigns.

Unsurprisingly, a study determined that the greater prevalence of firearms in circulation was strongly and positively correlated with higher rates of homicide, estimating that for every 18 guns taken off the streets of São Paulo, one life was saved.

Research into the characteristics of weapons used in crime is essential to guide public policy. Another recent Sou da Paz publication that covered every single weapon apprehended by the police in São Paulo (over 14,000 firearms) in 2011 and 2012 showed that a vast majority of the firearms used in violent crime were handguns, relatively low-tech, made in Brazil, and often fairly old.

Almost 60 percent of all weapons were revolvers, 32 percent were pistols; 78 percent were produced in Brazil (almost entirely by the company Taurus) and 14 percent were produced before 1980, including 2 percent produced in the 1950s -- only 10 percent were "new" (produced since 2010). Within the universe of weapons connected to homicides, almost 97 percent were handguns (revolvers and pistols).

Numbers and proportions will differ elsewhere, and the inclusion of firearm suicides and accidents under the rubric of 'armed violence' would further consolidate the disproportional role played particularly by handguns in the broader 'epidemic'. Most data on 'armed' or 'gun' violence does not include the massive numbers of gun suicides -- for conceptual and methodological reasons -- but from the perspective of the loss of life and suffering, these cannot be ignored; in the US, for example, more people yearly kill themselves with guns than the number killed with guns by others.

In the case of non-lethal incidents and the psychological effects of armed violence (fear, threats, indirect victimization), guns are also the main tools of injury and intimidation in most of the world, for most people. Though precise numbers are hard to come by, and particularly psychological effects may often be dismissed, these are a major component of the global armed violence crisis.

According to the Small Arms Survey, as many as 7 million people around the world over the last decade could be living with firearm injuries in settings outside of armed conflicts. In the US, estimates point to three to six non-lethal victims per fatality. Injuries, moreover, often mask so-called "slow homicides," recorded as different types of morbidity (such as infection), but in reality originally caused by gun violence months or even years earlier.

Psychological effects are likewise grim, under-reported and widespread. In the case of our city, though homicides have fallen over 70 percent in the last decade -- a precipitous, historic drop sometimes referred to as the "São Paulo miracle" -- recent polls suggest that the vast majority of people actually think "violence" has increased -- armed robbery being a major culprit. According to a recent victimization poll, more than half of all Brazilians are "very afraid" of being killed, and almost a third believes they could be murdered in the next 12 months.

These psychological effects should not be ignored, as noted by Ashkenazi, "guns do not need to be fired to be effective... provided the willingness of the user to actually fire the weapon has been established." In the national psyche of Brazil, and most of Latin America and the Caribbean, said willingness is firmly established, either through personal experience or ubiquitous media coverage of violent crime.

Quite clearly, certainly in the Americas but also most of the world, firearms should be the principal focus for those attempting to curb violence through better safety, regulation and control of its 'tools'. If indeed guns "kill and injure more on a daily basis worldwide than any other type of technology developed by humans to harm other humans", attention from civil society and governments alike should be commensurate.