Mr. Miller was battling cancer, pneumonia and a heart condition, according to the New York Post, which first reported the writer's illness on Feb. 11. He had been receiving hospice care at sister Joan Copeland's New York apartment but, earlier this week, asked to be taken by ambulance to his longtime home in Roxbury, Connecticut. He died Thursday night.

Mr. Miller, a gruff, robust presence at the many recent New York revivals of his dramas, has been a mainstay in the American theatre since the late forties, when Broadway productions of All My Sons and Salesman made his reputation as a serious-minded playwright. His other works include The Crucible, A View From the Bridge, After the Fall, Incident at Vichy, The Price and The American Clock.

After a period in the 1970s and 1980s when Mr. Miller fell out of favor with the critics, his star rose again in the late nineties with acclaimed revivals of A View From the Bridge, Death of a Salesman, The Price and The Crucible—all four were nominated for Tony Awards, with the first two winning—as well as the Broadway debut of a new play, The Ride Down Mt. Morgan and the reclamation of his first, obscure work, The Man Who Had All the Luck, which was acclaimed in a 2002 revival at the Roundabout Theatre Company.

Mr. Miller's last known original work, Finishing the Picture, had its world premiere in fall 2004 at The Goodman Theatre. Robert Falls, who helmed Death of a Salesman recently at the Goodman and on Broadway, directed. The starry cast featured Harris Yulin, Frances Fisher, Stacy Keach, Stephen Lang, Linda Lavin, Matthew Modine, Scott Glenn and Heather Prete.

The script was inspired by the story of former wife Marilyn Monroe's last movie, 1961's "The Misfits," which was directed by John Huston, and for which Mr. Miller penned the screenplay. During filming, Monroe was struggling with depression, unwieldy moods and substance abuse. The Goodman described the play this way: "A distinguished director is about to lose his picture due to the unstable behavior of a famously fragile movie star. She's recognized all over the world, loved by millions, but unable to believe in herself. The studio owners are threatening to pull the plug, and a temperamental acting teacher is flown in to coax the actress out of bed and onto the set."

Upon learning of Mr. Miller's death, director Robert Falls, told Playbill.com: "He had such joy and drive and pleasure in his work, and an engagement in the world. It never felt like working with a legend, it felt like working with a colleague. A greater fortune for me was not working on Death of a Salesman, but working on his last play Finishing the Picture. He treated them exactly the same. They were two plays where he couldn't wait to hear the laughter and applause of the audience. I feel a bit like I've lost my compass [with his passing]. His sense of the world and sense of what is right with the world was great."

He continued, "He is to me one of the giants. He, along with Williams and O'Neill, created the serious American play in America. They were fortunate enough to do it at a time when the culture appreciated them on Broadway."

Of Mr. Miller's influence, Falls said, "I think of as children of Miller — Tony Kushner, David Mamet and August Wilson. I take those three names off the top of my head as playwrights who stand on the shoulders of Arthur Miller."

Falls continued, "I think for us in the theatre, it's not just Arthur Miller's art. It's the way Arthur Miller lived his life in the world. He defines liberal in the absolute best sense of that word. This is a man who saw the Depression, World War II, the Holocaust, the Cold War, the fall of Communism. All these events were grist for his mill. And he always wrote about these things with a moral sense. He lived the way he wrote."

After a 16-year marriage to Mary Grace Slattery, Mr. Miller married movie star Marilyn Monroe in 1956. They divorced in 1961. His 40-year marriage to Inge Morath ended with her death in 2002.

Mr. Miller was born in New York City, on 112th Street in Manhattan, in 1915. He was one of three children in a middle-class Jewish home headed by his immigrant father, who was a manufacturer of women's coats. Mr. Miller attended high school in Brooklyn and worked in warehouses as a loader and shipping clerk to save money for tuition to the University of Michigan, where two of his plays were produced in 1934. He graduated with a bachelor's degree in 1938.

Mr. Miller granted permission to the University of Michigan for his only namesake theatre in the world. (There is no Arthur Miller Theatre on Broadway.) Groundbreaking for the new 250-seat space — designed to be a flexible space with recording booth, full scene and costume shops, dressing rooms and balcony — is set for 2005.

In an interview with the U-M alumni publication "Michigan Today," Mr. Miller stated he would like to write an inaugural play for the new theatre, but added, "It's easier to build a theater that will stand up than to write a play that will."

After graduating Mr. Miller began working with the Federal Theatre Project an wrote radio plays for CBS and the Cavalcade of America.

His first play on Broadway was The Man Who Had All the Luck in 1944. In 1949, in the wake of World War II, his All My Sons showed the world he was a writer who faced moral issues head-on: The play's focus is a manufacturer who knowingly allowed shoddy parts to be sold to the government in wartime, causing the death of pilots. The revelation rocks the foundation of his family, ending in further tragedy. Mr. Miller powerfully commingled the American victory in wartime with the dark side of American capitalism, and his career was launched.

He won the Pulitzer Prize with Death of a Salesman in 1949. The portrait of the past and present of a Brooklyn family headed by salesman Willy Loman was Mr. Miller's homage to his middle-class past. Struggling with delusions that he will be successful and well liked for many years to come, Willy shudders when confronted by job loss and his son's disgust for him.

"In a sense," he once said, "all my plays are autobiographical."

The 50th anniversary production of Death of a Salesman, in the 1998-99 Broadway season, started at Chicago's Goodman Theatre, was a smash in New York and later filmed for TV. Brian Dennehy played Willy, Robert Falls directed, and a new generation saw the crafty portrait of a dysfunctional American family. It won Tony Awards for Best Revival, Leading Actor in a Play (Dennehy), Featured Actress in a Play (Elizabeth Franz), Direction of Play (Falls).

Willy Loman was a universal character, Dennehy said at the time. "I'd come out of the Goodman [Theatre], and there'd be these guys waiting —- successful guys, beautifully dressed, gray hair, tears pouring down their face, their wives standing behind them, really worried because they've never seen the guy like this before. I can't tell you how many times I heard, 'That's my father you've put up there. Or my uncle.' One of the reasons the audience finds it so moving and compelling is that it's intersecting with things they have felt or suspected or understood about themselves. That's certainly true for me, and when you're up there acting it out, there's a psychic cost that has to be paid."

The Crucible, from 1953, was a parable that sprang from Mr. Miller's experience witnessing (and being swept into) the U.S. government's campaign to root out communists from all aspects of American life, but most visibly, from the entertainment industry. The play focused on the Salem, Massachusetts witch hunts and the shattering effect they had on the innocent.

Of the time of the early 1950s, when Sen. Joseph McCarthy was dragging supposed communists into hearings, Mr. Miller wrote, in his autobiography, "Timebends": "For me the spectacle was depressing, and not only for the obvious reasons. Certainly I felt distaste for those who groveled before this tawdry tribune of moralistic vote-snatchers, but I had as much pity as anger toward them. It bothered me much more that with each passing week it became harder to simply and clearly say why the whole procedure was vile. …The accused in 1950 and 1951 had not had a political connection since the late thirties or early forties, when in their perfectly legitimate idealism they had embraced the Russian Revolution as an advance for humanity. Yet the Committee had succeeded in creating the impression that they were pursuing an ongoing conspiracy."

In 1956 he appeared before the House Un-American Activities Committee and refused to name people at a meeting he had once attended, although he guessed that the meeting may have included Communists. He was convicted of contempt of Congress in 1957, although the Supreme Court overturned the conviction in 1958.

Although considered a thinly-veiled metaphor for the McCarthy hearings, the play is considered to be one of Mr. Miller's more universal works today. In it, Abigail Williams has an affair with married John Proctor. She accuses his wife of being a witch, and in defense of his wife the adultery is revealed. Liam Neeson and Laura Linney starred in a Tony Award-nominated Broadway revival of the play in 2001-02.

Of his bent toward the political, Mr. Miller, a frequent essayist, wrote, "I can no longer take with ultimate seriousness a drama of individual psychology written for its own sake, however full it may be of insight and precise observation. Time is moving: there is a world to make...a world in which the human being can live as a naturally political, naturally private, naturally engaged person, a world in which once again a true tragic victory can be scored."

The playwright said, "The play is about hysteria, public mass hysteria, and the attempts by certain interested parties to exploit that hysteria for their own profit. The threat of this kind of hysteria is never really gone. It's with us always."

The American playwright Edward Albee released this statement the morning of Feb. 11: "About a year ago Arthur Miller paid me a great compliment. He said that my plays were 'necessary.' I will go one step further and say that Arthur's plays are 'essential.' Arthur and I marched together several times to protest repressive governments. His work teaches us a lot about how to fight evil."

In 2000, the Roundabout Theatre Company revival of Mr. Miller's A View From the Bridge, directed by Michael Mayer, won the Tony for Best Revival. The 1955 play, about a tough Italian-American longshoreman, Eddie Carbone, in love with his niece, was originally paired with A Memory of Two Mondays. Mr. Miller later expanded and rewrote A View From the Bridge and it was staged Off-Broadway in 1965, running longer than the initial staging and prompting a wide life in regional theatre (it was revived in New York in 1983 with Tony LoBianco and then by Roundabout in 1997-98, when Anthony LaPaglia snagged a Best Actor Tony or playing Eddie).

Mayer directed a revised revival of Mr. Miller's After the Fall (about a man processing the events and people — including a Marilyn-like star —in his life) for the Roundabout Theatre Company on Broadway in 2004.

Roundabout also staged All My Sons Off-Broadway in 1974 and 1997 (the latter starring John Cullum as the corrupt and broken Joe Keller; the work won the 1998 Lortel Award for Best Revival). In 1987 it was revived on Broadway starring Richard Kiley. The work remains much-produced in American regional theatre.

Off-Broadway's Signature Theatre Company, which devotes each season to one writer, celebrated the work of Mr. Miller in 1997-98, offering the premiere of Mr. Peters' Connections. Mr. Miller wrote essays ("Tragedy and the Common Man"), short stories, screenplays and teleplays. His screenplays include TV's "Playing for Time," Hollywood's "The Misfits" (the picture starred Marilyn Monroe), "Everybody Wins" and his own film version of "The Crucible" starring his son-in-law, Daniel Day-Lewis. He was Academy Award-nominated for "The Crucible."

In 1965 he was elected president of P.E.N., the international society of writers.

In November 2001 he received the National Book Foundation's medal for distinguished contribution to American literature.

In 1999, he received a special Tony Award for Lifetime Achievement, one of many awards in a long career.

Survivors include daughter Rebecca Miller, a screenwriter and actress, and her husband Daniel Day-Lewis; sister Joan Copeland; and Agnes Barley, reported by the Post as Mr. Miller's 34-year-old girlfriend.