AT A TIME when America is focused on tales of repression abroad, the successful march of democracy through much of the developing world often goes uncelebrated.

Fortunately, Hans Janitschek, an Austrian journalist, has captured the evolution of freedom in my grandparents' homeland of Portugal in his timely biography of that country's newly elected president.

I have known M,ario Soares for only a relatively short while, but I have known of him for much longer. He is not only Portugal's most popular politician, he is the hero of all Portuguese Americans. To understand Portugal's transition from dictatorship to democracy is to know Soares, for they are one and the same. And from the opening chapter, Janitschek relates how the struggle for independence hinged on the courage and wisdom of this one great man.

"I sensed a certain restlessness. Was it the beginning of a storm?" Janitschek recalls thinking during his secret visit to Lisbon in 1969. He had come as secretary general of the Socialist International, an influential group of mainly European democrats, to see Soares, key opponent of the "iron fisted" Salazar regime.

It was a risky venture: Soares, jailed a dozen times on political grounds, had just returned from a year's exile. Salazar's secret police had him under constant watch. Certainly a covert meeting to review ideas for toppling the 41-year-old dictatorship was life threatening.

Nonetheless, Soares understood that without international credibility, his efforts to gain credibility with the masses at home would fail. The meeting with Janitschek proved worth the risk: Later that year, Olof Palme and Willy Brandt, among other European leaders, lent their valuable support to Soares.

Yet in 1970, the regime reacted predictably by deporting him again; he would not return until after the bloodless coup of 1974.

"In democracies governments fall when elections are lost. Dictatorships usually collapse when they lose a war," the author notes. Indeed, Portugal's colonial war in Africa had weakened the country so much that not even the conservative military would tolerate fascist rule any longer. General Antonio Spinola became president and named Soares as foreign minister. Still, it did not take long for a new threat, this time from the left, to emerge.

One of this book's strengths is how the author grasps the social and political consequences of revolution: "After 50 years of fascism the people welcomed its fall, but they did not really know how to handle the new situation. . . . A dictatorship had been abolished, but what next?"

The communists knew what to do. With backing from Moscow, they seizd control of many vital power centers. As a result, the government fell four times in the first three months of 1975. Spinola fled the country. The situation became so bad that Henry Kissinger wrote Portugal "virtually off the map of the West."

But Soares was convinced that workers did not want communism, so he quit the government and organized massive demonstrations. In late 1975, in his "most glorious moment," Soares literally faced down the communists on the streets of Lisbon. "There is no question that Soares, the man of peace, the human rights champion, was in these hours ready to fight." His opponents were not.

So not only did Soares defeat the communists, he "emerged as the man of the center, of reason, of unity." He never discriminated, he opposed undemocratic forces on the right and left. His reward was the establishment of a full parliamentary democracy in 1976, a Socialist Party victory and election as prime minister.

In the ensuing 10 years Soares faced many of the expected hurdles as leader of a new democracy. New political rivals and economic woes often forced him from office, but he deserves credit for many things: among them, advancing a modern, open society and joining the European Economic Community. But his most significant achievement has been the stabilization of democracy. Neither the far right nor left has been a serious threat since the crisis of 1975, and with Soares' election as president earlier this year, it is most unlikely they ever will be again.

JANITSCHEK'S WORK is brief -- just 116 pages -- but it is hard to think of any vital areas not covered. Chapters dealing with his "making" as a socialist, strong family ties and personal traits

help the reader understand what has motivated Soares, now 62, throughout his career. He is an "elegant but simple" man, always humble, never afraid. He dials his own telephone and, like his slain friend Olof Palme of Sweden, refuses all security measures.

The book contains few criticisms -- Soares sometimes went too international -- but there is no question the work is credible. Janitschek relates his intimate contact with Soares, his important friends and family in a convincing way.

This is the story of a man who first said "no" to the fascists at 12, who married his wife while in jail, who cried only once in his life and who, like the Portuguese on both sides of the Atlantic, is incurably optimistic: "Nada o abate -- nothing gets him down."