Peter R. Scanlon, a former chairman and chief executive of one of the world's largest public accounting firms, died on Dec. 3 at his home in Jupiter, Fla. He was 78. The cause was cancer, his daughter Barbara Scanlon Jessup said. Scanlon led Coopers & Lybrand from 1982 to 1991; the firm merged with Price Waterhouse in 1998 to form PricewaterhouseCoopers. During his tenure, the company was regularly referred to as one of the Big Eight. But with consolidation in the industry, and with Arthur Andersen out of business, PricewaterhouseCoopers is now one of the Big Four. In the late 1980s, under Scanlon, Coopers & Lybrand often drew criticism for shunning the merger mania that engulfed the accounting profession. Ultimately, however, the firm was credited with having turned the situation to its advantage. By attracting disaffected affiliates of its competitors in other countries, it was able to expand its international franchise without incurring the costs of all-out mergers. 'We're not opposed to mergers, but we're just not going to do it because everyone thinks it's the right thing to do,' Scanlon told The New York Times in 1989. Scanlon brought in major new clients, including SmithKline Beckman and Unilever, and expanded his company's existing operations rather than opening new offices. In the process he steered its profitability close to that of the other big firms. In 1991, his last year as its leader, Coopers & Lybrand earned $261 million on revenues of $1.5 billion. Peter Redmond Scanlon was born in the Bronx on Feb. 18, 1931, one of eight children of Loretta Ryan and John Scanlon Jr. His father, who owned an insurance company, died when Peter was 9. Peter was the first in his family to graduate from college, earning a bachelor's degree in accounting from Iona College in 1952. He immediately joined what was then known as Lybrand, Ross Brothers & Montgomery. After serving in the U.S. Navy during the Korean War, he returned to the company and began rising through its ranks. Besides his daughter Barbara, Scanlon is survived by his wife of 56 years, the former Mary Jane Condon; another daughter, Janet Scanlon; two sons, Peter and Brian; and eight grandchildren. His son Mark died in 1992. 