Fifty years ago, when the American Telephone and Telegraph Company still held a monopoly on U.S. phone service, the first minute of a toll call could easily cost a dollar—the equivalent of about $5 today. But a few pennies of that 1950s dollar supported research and development efforts at Bell Telephone Laboratories and at AT&T’s manufacturing arm, Western Electric.

A version of this article appeared in the December 2005 issue of Harvard Business Review.