In their 1999 book, “The Trust: The Private and Powerful Family Behind The New York Times,” Susan E. Tifft and Alex S. Jones said that Mr. Sulzberger had long had his eye on Mr. Mattson as president of the company.  “He liked Mattson’s straightforward approach to problems, his encyclopedic grasp of business and production details, his stability and dedication, and his firm, decisive manner,” the authors wrote. “He also knew that Mattson had the hands-on operational experience he considered essential to lead a company of growing complexity.”  Mr. Mattson’s first major coup as The Times’s executive vice president and general manager was to negotiate a landmark 1974 agreement with the printers’ union. It was the death knell for 19th-century Linotype machines, which cast type in hot lead, and opened a new era of computerized-electronic typesetting at the paper. In exchange, The Times guaranteed lifetime employment for 800 printers, whose jobs disappeared through attrition.  The 11-year agreement, with Local 6 of the International Typographical Union — it also covered The Daily News and its 600 printers — gradually ended restrictive and wasteful union work rules that duplicated many printing tasks, and it enabled The Times to cut costs sharply at a time of stagnant circulation and advertising revenues in a national recession, which had hit New York City particularly hard.  In the mid-1970s Mr. Mattson, working closely with Mr. Sulzberger and Mr. Rosenthal, introduced striking and profitable changes in the newspaper’s appearance and content, switching from eight news columns on a page to six, and expanding the weekday Times from two sections to four. The six-column measure gave the paper an airier, more open and modern look, making it easier to read. But the changes were not just cosmetic.  The four-section paper was a radical transformation. The first part carried foreign and national news, while two sections were given to metropolitan and business-financial news. The fourth inaugurated a cornucopia of feature sections that were different for each weekday: Sports on Mondays; Science on Tuesdays; Living on Wednesdays; a Home section on Thursdays; and Weekend, an arts and entertainment section, on Fridays.  The Times also introduced four Sunday regional sections aimed at New York City’s affluent suburbs in New Jersey, Long Island, Westchester County and Connecticut.  The changes spurred advertising and feature articles on suburban localities, and on food, gardening, entertaining and other topics. Some critics said pieces on penthouse deck furniture and high-end cooking undercut the paper’s reputation for serious journalism, but defenders said they took no space away from regular news and brightened the tone of The Times.  In any case, the sections proved popular with readers and advertisers, and some media historians called them collectively the most important redesign of the paper since its purchase by Adolph Ochs in 1896.  In 1976, Mr. Mattson announced plans to computerize The Times’s newsroom, and over the next two years writers and editors surrendered typewriters for bulky computer terminals that sped the processing of news.  The last major labor-management dispute negotiated by Mr. Mattson was an 88-day pressmen’s strike in 1978 over demands by The Times, The News and The New York Post to cut the number of workers operating their presses. It ended with smaller staff reductions than the newspapers had sought and cost $150 million in advertising and circulation revenues. But the papers won concessions that insured long-term profitability and eventual control over their own pressroom operations.  Mr. Mattson brought another long-planned project to fruition in 1980: a national edition of The Times, edited in New York and transmitted by satellite to Chicago for same-day distribution in the Midwest. Two years later, The Times began beaming its national edition to California for same-day distribution to major cities in 13 Western states. Two decades later, the national edition accounted for more than half the print paper’s circulation.  Mr. Mattson was named president when Mr. Sulzberger gave up the title in 1979 and formally took over the chief operating officer’s duties that he had been handling for years. He went on to diversify company holdings with dozens of broadcast, newspaper and magazine properties in the 1980s.  Before retiring, he was a forceful advocate of The Times’s purchase of The Boston Globe in 1993 for $1.1 billion, a transaction much criticized in leaner years. (In 2013, The Times sold The Globe and its other New England media properties to John W. Henry, principal owner of the Boston Red Sox, for $70 million.)  “Walt was a wonderful business partner for my father,” Arthur Ochs Sulzberger Jr., The Times’s current publisher and chairman, said in an email on Friday. “He was kind and always straightforward, which Dad greatly valued, as did I in the few years we overlapped in management at The Times.”  Walter Edward Mattson Jr. was born in Erie, Pa., on June 6, 1932, to Walter Mattson and the former Florence Anderson. As a boy, he delivered papers for an uncle’s weekly in Erie. His father worked for the National Biscuit Company and was transferred to various cities, including Portland, Me., where Walter Jr. graduated from Deering High School in 1949.  After two years in the Marine Corps, he worked nights as a printer at The Portland Press Herald while attending Portland Junior College and then Portland University, where he received a bachelor’s degree in business and accounting in 1955.  He married Geraldine Anne Horsman in 1953. Besides his wife, he is survived by two sons, Stephen and William; a daughter, Carol Heylmun; a sister, Norene Hastings; eight grandchildren, and one great-grandchild.  In the mid-1950s Mr. Mattson was an advertising manager for a newspaper in Oakmont, Pa., and a production assistant at The Boston Herald Traveler. After earning an electrical engineering degree from Northeastern University in 1959, he joined The Times in 1960 as an assistant production manager. He became a vice president in 1970, attended summer advanced management programs at Harvard Business School and within three years was general manager, in charge of all business, marketing, circulation, personnel and production operations.  Mr. Mattson oversaw years of solid profit growth in the 1980s, although The Times’s financial performance weakened late in the decade. In 1992, seven months after Arthur Sulzberger Jr. succeeded his father as publisher of The Times, Mr. Mattson stepped down as president and was named vice chairman. He worked with the younger Mr. Sulzberger on strategic planning before retiring in 1993.  Mr. Mattson had a home in Sarasota and had for many years lived in Stamford, Conn. Since 2013, he and his wife had lived at the Plymouth Harbor retirement community in Sarasota. He was a member of the Times company’s board of directors in the 1980s and early 1990s.  A version of this article appears in print on December 31, 2016, on Page A21 of the New York edition with the headline: Walter E. Mattson, Former Times President, Dies at 84. Order Reprints| Today's Paper|Subscribe
Mr. Mattson, a production executive who had once been a printer, helped transform the newspaper with innovative labor agreements and new technologies.