PUTTING HEAVY emphasis on economic growth, Secretary of the Treasury James A. Baker urges the world to stick to its present strategy for managing Latin America's debts. Growth is the key to this debate. Some of the Latin countries, led by Brazil, argue that they need sweeping reductions in their debts to enable their economies to grow. Mr. Baker responds that most of these countries are now getting along pretty well and any debt reduction -- a euphemism for partial default -- would threaten their future development. The evidence supports Mr. Baker.

Among the Third World's biggest debtor countries, growth now averages about 3.7 percent a year, a good deal higher than in this country. And their export earnings are rising. Mr. Baker spoke at the meetings here of the World Bank and the International Monetary Fund -- an audience including quite a few people who wanted to see the United States and the other rich countries change their minds about concessions on the debts. But if the goal is continued growth, the debts have to be handled in ways that preserve these countries' access to international trade and finance. That's how countries get rich. Mr. Baker did not need to point out that many Latin countries in the past have experimented with economic isolationism and import substitution -- experiments that may have enriched a few people, but did it at the expense of their countries and their fellow citizens.

While things are moving in essentially the right direction, Mr. Baker had several improvements to suggest. He is evidently concerned by the adversary relationship that has evolved between some of the developing countries and the IMF, in its role as financial policeman. He gently nudged the IMF to give more attention to these countries' long-run prosperity, while working on their short-run deficits. He proposed setting aside resources within the IMF to cushion unpredictable shocks like earthquakes, sudden drops in commodity prices and sudden rises in interest rates.

It's been just two years since the secretary, at a similar meeting, laid out what has become known as the Baker plan for the Latin debts. While sticking with the essential points of the plan, he was also trying to acknowledge some of the debtor countries' grievances. The Baker plan is proceeding more slowly than its author expected, chiefly because the rich countries' growth rates -- and the markets for Latin exports -- have expanded less rapidly than he had assumed. But if progress has been slower than he hoped in 1985, it is still progress and it is substantial