To control soaring health care costs, many U.S. corporations have rolled out wellness programs on the idea that encouraging employees to adopt a healthy lifestyle would lead to fewer trips to the doctor and fewer missed work days. According to a survey by the Society for Human Resource Management, about three-quarters of HR professionals said their organizations offered some sort of a wellness program in 2014. While more than two-thirds of these respondents reported that such programs were “somewhat effective” or “very effective” in reducing health care costs, a closer look at other studies finds that the outcomes for these programs are not so clear. This suggests corporations should rethink wellness programs, bearing in mind that several other critical factors besides lifestyle predict a healthy life.

It’s hard to believe, but not quite four decades ago the Chinese settlement of Shenzhen was a modest fishing village, with a population of roughly 30,000. Today, thanks to a policy begun in 1979 that was designed to encourage foreign investment, that sleepy village is a manufacturing hub with a population of roughly 10 million. The success of Shenzhen is consistent with the broader development of China’s Pearl River Delta. Once mostly agricultural land, it has become, according to a recent World Bank report, the largest urban area in the world. The cities in the region have a combined population of about 57 million—larger than the populations of many countries, including Canada, Argentina, and South Africa.

Fifteen years ago, at 8:46 a.m. on September 11, 2001, American Airlines Flight 11 crashed into the North Tower of the World Trade Center, followed, 17 minutes later, by United Airlines 175, crashing into the South Tower. Two other planes, American Airlines 77 and United Airlines 93, were also hijacked that day, crashing respectively into the Pentagon and into a field in Pennsylvania. Nearly 3,000 people died on September 11, 2001, and about 6,000 people were physically injured. The immediate aftermath of the attacks cost at least $10 billion in property damage and about $3 trillion in total costs. The long-term global consequences of the attacks continue to be felt to this day—9/11 resulted in the launch of global wars in Iraq and Afghanistan, with about 500,000 people dying in Iraq and likely a comparable number of deaths in Afghanistan. In many ways, 9/11 changed everything: We continue to face what feels like an interminable string of terrorist attacks, that kill dozens of people at a time, despite a wholesale upgrading of security measures worldwide.

In an 1818 letter to his brothers, a former medical student, and burgeoning poet, named John Keats described what he considered to be the most important quality possessed by “a man of achievement.” He called it “negative capability” and defined it as “when a man is capable of being in uncertainties, mysteries, doubts, without any irritable reaching after fact and reason.”

For millions of people, Sept. 11, 2001, was the first mass disaster experienced in real time. Many who watched the event unfold on television can still remember with great clarity, as the 15th anniversary approaches, where they were, and how they felt, on that terrible day.

I was in New York City on 9/11, just starting my career as an epidemiologist. Along with countless other New Yorkers, I watched with horror as the World Trade Center towers collapsed. Stunned by the destruction, our research team quickly became concerned with the potential long-term mental health consequences of the attacks.

The U.S. has substantially worse health outcomes than all its peer nations. In a list of non-communicable disease mortality in 17 high-resource countries, the U.S. has the second-highest death rate at 418 deaths per 100,000 people.

Next week marks the 11th anniversary of Hurricane Katrina, which swept through the Gulf Coast of the United States. The storm breached levees, led to extensive flooding, and displaced hundreds of thousands of people in Alabama, Louisiana, and Mississippi. The hurricane would ultimately kill more than 1,800 people, and inflict over $100 billion in damage. Particularly hard hit was the city of New Orleans.

The issue of gun violence has reached, it seems, epidemic proportions. Since taking office President Barack Obama has addressed the nation 14 times in the wake of a mass shooting. In June, House Democrats staged a sit-in to protest the lack of national legislative movement on gun control. Despite these efforts, there has been little progress on this issue at the federal level, and the partisan divide remains as wide as ever. Presidential candidate Hillary Clinton supports a range of gun reforms, including an assault weapons ban, while candidate Donald Trump calls gun bans “a total failure.”