Last Friday saw the formal adoption of the Sustainable Development Goals at a special summit of the United Nations. Standing atop its exhaustive and unwieldy agenda is a singular objective: to end extreme poverty by 2030.

Extreme poverty is defined by the parsimonious $1.25 a day poverty line to capture only the most egregious forms of destitution: where people live so precariously that they fret about the source of their next meal and are burdened by the simple stresses of survival. Were this kind of poverty really to be eliminated, it would hardly imply a world of universal prosperity; hardship and deprivations of various kinds would remain commonplace. Nevertheless, it would represent a key milestone in human progress.

Inspiring though this goal is, it is not new. In fact, it has been pledged many times in the past. That suggests achieving the goal may be harder than we think.

Despite the strong progress there has been in reducing extreme poverty over the last generation and more, an extrapolation of past trends is problematic. What worked to reduce poverty in certain countries won’t necessarily work for others. Global factors that supported poverty reduction in the past are expected to change.

In other words, the last mile in ending extreme poverty looks different from the miles already traveled. These differences are explored in a new book I co-edited with Homi Kharas and Hiroshi Kato. We argue that ending extreme poverty will require a stronger focus on securing peace, creating jobs, and building resilience. The book explores what works in tackling these three issues so the last mile might successfully be completed.

The Creative Lab at Brookings has put together a neat little video describing the book’s themes. I encourage you to watch the video and if you enjoy it, to read our book.