FOLLOW THE MONEY.

• Author: Castillo, Tessie
• Position: Brief article

Drug treatment and rehabilitation is now a multibillion-dollar-a-year industry in the United States. Just a few years ago, in 2011, private equity firms invested $11.4 million in drug detox and treatment centers. Five years later, in 2016, that number had leapt to $2.9 billion. Investors are snapping up drug rehabs, outpatient facilities, sober living homes, and urine labs, aiming to consolidate a once fragmented industry.

To give one example, over the last decade, Bain Capital, a company founded by former presidential candidate Mitt Romney, bought a chain of treatment centers and methadone clinics for more than $720 million before selling the package to a company called Acadia Healthcare. Now one of the largest companies in the industry, Acadia has been buying up treatment centers at a breathtaking pace. The company owned six facilities in 2010; by 2016, it owned 587.

Fortune 500 companies are paying close attention. Forbes magazine has called drug treatment a "healthy and growing commercial industry," noting the emergence of the American Addiction Centers as the first...