Few software experts have had as revolutionary an influence on the development of computing as Charles Simonyi, and few have been so richly rewarded for their efforts. As a scientist at Xerox's Palo Alto Research Center in the 1970s, Simonyi invented Bravo, the first word-processing program that showed on-screen exactly how a document would look in print-a concept commonly referred to as "what you see is what you get." Simonyi then joined Microsoft, when it was still a startup with three dozen employees. There he became the company's chief architect, piloting the development of both Word and Excel. Along the way, he also became a billionaire: Forbes recently listed him as the 209th richest person in the United States.

Last year Simonyi abruptly ended his 21-year tenure at Microsoft to start a company of his own, Intentional Software, which he has, to date, funded entirely with his own money. In one sense, Intentional Software is a modest company with modest goals; Simonyi does not expect to have a product to sell for several years. But in another sense, his goals are so large that the word "ambition" barely does them justice. Simply put, Simonyi wants to save software from its own complexity-so that the true potential of computer technology can at last be realized.

Grand quests are something Simonyi knows a lot about: he left Hungary to study abroad at the age of 17 and-illegally-never returned. While he still speaks with a faint accent, he also expresses his opinions unequivocally, without any searching for words, especially when talking about his favorite subject.

Software "has become a field where we focus on incremental improvements in processes," he says. "That course is futile, because it can never solve the problem of human imperfection."