AS it turned 100 last week, I.B.M. was looking remarkably spry. Consumer technologies get all the attention these days, but the company has quietly thrived by selling to corporations and governments. Profits are strong, its portfolio of products and services looks robust, and its shares are near a record high. I.B.M.’s stock-market value passed Google’s earlier this year. Not bad for a corporate centenarian.

Yet, not so long ago, I.B.M.’s corporate survival was at stake. In the early 1990s, it nearly ran out of money. Its mainframe business was reeling under pressure from the lower-cost technology of personal computing.

New leadership was brought in, and thousands of workers were laid off. It was part of the company’s painful journey to what might be called “post-monopoly prosperity” — that is, a new path to corporate success once a dominant product is no longer the turbocharged engine of growth and profit it once was.

“I.B.M. faced the challenge that all great companies do sooner or later — they dominate, they lose it, and then they re-create themselves or not,” observes George F. Colony, the chief executive of Forrester Research.