Bruce Wasserstein

Bruce Wasserstein, the Wall Street investment banker who helped pioneer the hostile takeover in the 1980s and reshaped the mergers and acquisitions business into a high art, died Wednesday.

Mr. Wasserstein, 61, was the chairman and chief executive of Lazard. The cause of death could not be immediately learned, though he had been hospitalized earlier this week for what was described as an irregular heartbeat. The company had described his condition then as serious, but said he was “stable and recovering.”

Mr. Wasserstein, who began his career as a lawyer but quickly moved into investment banking, worked on some of the biggest deals of the past three decades, including Kohlberg Kravis Roberts’s takeover of RJR Nabisco.

Mr. Wasserstein rarely looked like a stereotypical investment banker, preferring a rumpled look, his shirt often untucked. But he transformed deal-making from a business built on relationships, as practiced by forebears like Andre Meyer and Felix G. Rohatyn of Lazard, into one more akin to war, built on complex tactics and armies of bankers and lawyers.

Bruce came to the M&A world as a lawyer at the New York law firm Cravath, Swaine & Moore, but left to become an investment banker, at First Boston Corp., where he and Joseph Perella, another top Wall Street banker, built its M&A practice. The two men left First Boston to start Wasserstein Perella & Co in 1988.

In his book, Cohan wrote that Bruce Wasserstein bred a mythology of a “disheveled, overweight Einstein” with a large ego.

The New York Times compared Wasserstein and Perella to the “Simon and Garfunkel of the merger and acquisitions business. They are a poet and a one-man band; the abrasive and brilliant tactician and the immensely likable supersalesman with one major product on his shelf: Bruce Wasserstein.”

As a banker, Wasserstein achieved his great fame as an adviser to buyout house Kohlberg Kravis Roberts & Co. on its acquisition of RJR Nabisco in 1989, later documented in the book, “Barbarians at the Gate.” It was back then that he earned the nickname “Bid ‘em Bruce ” (later shunned), famously daring clients to “be great” and pay up for acquisition targets.

In 2000, Mr. Wasserstein sold his boutique investment bank Wasserstein Perella & Co. to Germany’s Dresdner Bank for $1.5 billion.

Ever the inveterate deal-maker, much of those proceeds went to him.

In 2002, he was hired by Lazard’s Michel David-Weill, then the firm’s chairman, to run the investment bank he had long admired. Mr. Bruce Wasserstein, however, persuaded many of the firm’s deal-makers to support one of the biggest deals of his career: taking Lazard public and ending more than a century of private ownership. The move set off a bitter feud between the two men, one often played out in the press.

Soon after Lazard went public, Mr. Wasserstein embarked on another major deal, aiding Carl C. Icahn in trying to shake up AOL Time Warner, his former client. However, that effort ended quietly, with the company reaching a compromise with the gadfly investor.

Most recently, he has led the team advising Kraft in its potential takeover of Cadbury.

But Mr. Wasserstein had interests beyond the boardroom. In 2004, he made a surprise bid for New York magazine, defeating some of the city’s richest businessmen in the process. Years before, he purchased a passel of trade publications including The Deal, a trade publication aimed at deal-makers, and American Lawyer, one aimed at the legal field. He sold the magazine group to Incisive Media, a British publisher, in 2007 for $630 million.

Mr. Wasserstein is survived by his wife, Angela Chao, and seven children. He adopted the daughter of his late sister Wendy. He has been divorced three times.