Born in New York City in 1926, Greenspan earned his Bachelor's and Master's degrees in economics at NYU. He worked toward a Doctorate in economics at Columbia before leaving for a full-time job at the National Industrial Conference Board, a leading association of business executives.

In his 20s and 30s, Greenspan was invited into Ayn Rand's inner circle and attended weekly discussion groups in her New York apartment. Rand, author of The Fountainhead, preached a fire-and-brimstone philosophy of pure, free market capitalism: no-holds-barred competition, she insisted, sorts the fit from the unfit; the deserving from the undeserving; the foolish from the wise. Any "interference" in the markets -- by government, trade unions or anyone else -- is a social poison to be resisted and purged.

In the 1950s, Greenspan formed the Townsend-Greenspan consulting company, attracting such big-name clients as Alcoa, Owens Corning and U.S. Steel. 

"There was an absolute rule at Townsend-Greenspan," recalls Lowell Wiltbank, a fellow Rand-ite who worked at the company. "No communication that came out of the firm should ever be interpreted to advocate any expansion of government interference in the economy. If we advocated anything in terms of government policy, it was deregulation."

By 1968, Greenspan had moved to the center stage of national politics, serving as Richard Nixon's coordinator of domestic policy research during his successful presidential campaign. Nixon subsequently appointed Greenspan Chairman of the Council of Economic Advisers, a position he continued to hold under Republican President Gerald Ford.

Greenspan advised Ronald Reagan during the 1980 presidential race, after which Reagan appointed him to chair a special commission on Social Security. 

In 1987, Reagan named Greenspan Chairman of the Federal Reserve Board, where he has continued to serve through a series of Republican and Democratic administrations.