By JUSTIN GILLIS

The Bill and Melinda Gates Foundation has brought a distinctive approach to problems of global development: a sense of urgency, a willingness to make big investments in pursuit of ambitious targets, and — above all — a hard-nosed insistence on results that can be counted and documented. The Gateses, who are heavily involved in managing the foundation that bears their name, take the view that setting explicit numerical targets and holding people to them is one key to progress.

Now Mr. Gates is calling for a stringent application of that approach in the field of global agriculture. In a speech Thursday morning in Rome, he called on the United Nations agencies that deal with world food supply to set a global target for the productivity growth of agriculture.

He did not specify what the target should be, presumably leaving room for experts to weigh in on what is achievable — and for horse-trading among the affected agencies. But he outlined a strategy that would include scorecards of progress against which agencies (and possibly whole countries) could be measured, creating a sort of race to improve. And he wants this plan in place by the end of the year.

It will be hard to know exactly how ambitious the plan is until we know the numerical target, and I for one will be watching what emerges over the next few months.

We do know that productivity growth in global agriculture peaked at almost 3 percent a year during the period known as the Green Revolution, the three decades that ended roughly in 1990. That meant output was growing faster than population and global hunger was falling.

Lately, for a number of reasons, including a decline of public investment in agriculture, a drag on farm output from climate change, and other problems — productivity growth has fallen to something closer to 1.5 percent. The growth rate, in other words, has dropped nearly in half. Prices of basic foodstuffs have soared, global food stocks are low and millions of people have been pushed into food insecurity.

In his speech, a text of which was provided early to The New York Times, Mr. Gates offered some tough-love criticism of the United Nations food agencies, which include the Food and Agriculture Organization, the International Fund for Agricultural Development and the World Food Program. Their efforts in the past have been poorly coordinated, Mr. Gates said, without enough focus on measuring results and figuring out what actually works. But new leadership has taken control of several of these agencies, and Mr. Gates appears to be using the moment to try to point them in a fresh direction.

“The world’s agriculture and food system is now outdated and inefficient,” Mr. Gates said in the speech. “Countries, food agencies and donors aren’t working together in a focused and coordinated way to provide the help small farmers need, when they need it.”

There is not much mystery about what poor farmers need: simple inputs like fertilizer and improved seeds, as well as better access to markets and improved food storage. Some African countries have already shown that significant progress is possible. In his speech, Mr. Gates announced fresh grants of $200 million to pursue agricultural work, bringing the Gates Foundation’s commitment to agriculture to about $2 billion.

In the next few months, we may find out if the world is really ready to establish a plan to improve the food supply and then carry it out.