Forrest Mars Sr., 95, the architect and patriarch of an international candy and food conglomerate who created one of the world's great fortunes from the likes of M&M candies and Milky Way candy bars, died Thursday at his home in Miami, Mars Inc. announced yesterday from its McLean headquarters.

Mr. Mars joined his father in a family-operated candy business in the 1920s, and over the years, he built the enterprise into a worldwide confectionary giant. After his retirement, his two sons, Forrest Jr. and John, working from the company's central office in McLean, directed one of the Washington area's largest locally based commercial and manufacturing operations, with global sales of $15 billion and a work force of 30,000 around the world. Its products include Skittles, Dove, Snickers and Three Musketeers candy brands, Uncle Ben's Rice, Kal Kan, Pedigree and Whiskas pet foods and Combos, Kudos and Twix snacks. The Mars family is said to be among the richest in the United States.

In keeping with a long-standing policy of shunning public exposure, Mars Inc. said no details would be released about Mr. Mars's death. During his years in business, Mr. Mars was known as a maverick who refused to join the trade organizations of his industry, and he shunned inquiries by the trade and general media, a practice followed by his sons and current Mars executives, who generally decline to answer questions from the media or release information about the company or themselves.

"Mars's assets are often underestimated because the company is as loose with its information as its McLean, Va., neighbor, the CIA," Forbes magazine said in 1988.

Mr. Mars took credit for the idea that resulted in the Milky Way in his early years as a candymaker. He said he told his candymaker father, Frank Mars, in the early 1920s to "put this chocolate malted drink in a candy bar. . . . I was just saying anything that entered my head. And I'll be damned if a short time afterward he has a candy bar. And it's a chocolate malted drink. He put some caramel on top of it and some chocolate around it -- not very good chocolate -- he was buying cheap chocolate -- but the damn thing sold," he was quoted as saying by Joel Glenn Brenner in her book, "The Emperors of Chocolate." In 1924, Milky Way's first year on the market, its sales totaled $800,000.

After running a candy operation in England during the 1930s, Mr. Mars returned to the United States in 1939 and in 1940 opened an M&M factory in Newark. This candy was modeled after a British confection, a tiny circle of chocolate encased in a protective crunchy coating, and the M&Ms came in a variety of colors. Peanut M&Ms made their debut in 1954. To several generations of Americans, they were promoted as "the candy that melts in your mouth, not in your hand," and they were made to survive through the heat and humidity of an American summer. "In those days, the stores didn't have air conditioning, the cars didn't have air conditioning, the homes didn't have air conditioning," a Mars spokesman said at the M&M 50th anniversary in 1990.

In his business conduct, Mr. Mars was said to be blunt and forceful, a demanding boss with a dominating personality and a volcanic temper, given to tantrums and tirades when something displeased him. In the business place, he was said to have ruled by fear, and he was known to be difficult to work for. But he cared only about performance on the job, not style or personality, and his evaluations were never arbitrary or subjective. Many of his top managers stayed with him over the course of their careers.

"What he lacked in charm he made up for in determination. Forrest was a risk taker with an uncanny ability to sense potential," Brenner wrote in her book.

He was almost fanatical in his insistence that extravagance be avoided at all costs, and he passed this policy along to his sons. Mars executives were expected to travel coach class on airplanes, make their own telephone calls and do their own document copying. Instead of having private offices, they all shared a work space. They were expected to clock in each day. Executive staffing was kept to a minimum, and the use of company-owned cars was discouraged.

Forrest Mars was born in Minnesota, where his father was just getting started in a small candy business outside Minneapolis. His parents divorced when he was 6 years old, and his mother sent him to live with her parents in North Brattleford, an isolated mining town in Saskatchewan.

After high school, he won a partial scholarship to the University of California at Berkeley, and he took a summer job as a traveling salesman of Camel cigarettes. In the course of his travels, he was reunited by chance with his father, and he left college to join him in a candy business.

He later decided to return to college, and he transferred to Yale, where he said he read every book he could find about the DuPont chemical company and John D. Rockefeller. He earned spending money by selling neckties to football players and Camel cigarettes to everyone he could.

He graduated in 1928 and rejoined his father in the candy business, but they had a falling out in 1932, and Mr. Mars left for Europe, where he started a confectionary operation in England in 1933.

After he returned to the United States in 1939, Mr. Mars presided over the growth of the M&M operation and expansion into other candies and foods. He ran his businesses from Chicago and New Jersey and first came to the Washington area in the early 1950s. In 1964, he acquired his father's old candy company from his father's heirs, and he merged it with his own operation. In 1973, he retired and left the business to his sons, but he then started a new candy operation in Las Vegas. Mars Inc. subsequently acquired that business.

In an interview last night, Brenner said Forrest Mars Jr. retired from the company in April, without public announcement.

Audrey Mars, the wife of Forrest Mars Sr., died in 1989.

Mr. Mars's survivors include his two sons and a daughter, Jacqueline.

CAPTION: Forrest Mars Sr., left, who joined his father's candy business in the 1920s, "was a risk taker with an uncanny ability to sense potential," one author wrote.