Jonathan Schwartz's office in Carnegie Hall used to be the studio of his father, Broadway and Hollywood composer Arthur Schwartz. "He wrote music in here," says Schwartz. "I inherited it when he moved to London in the early 1970s. The piano was right over there, and I spent years in here rehearsing with my pianist, Tony Monte."

In 1978, shortly after he finished his first novel, Distant Stations, Schwartz accepted an invitation from Michael's Pub in New York to perform songs by his father and other creators of the classic American popular music he loves. The two-week gig sold out, and for many years he enjoyed an agreeable sideline as a cabaret singer while continuing to write fiction (Random House released The Man Who Knew Cary Grant in 1988) and to host his innovative New York radio show, which he describes in his new memoir, All in Good Time (Forecasts, Jan. 26), as "just me and the music—Sinatra, Basie, Fred Astaire, Ella Fitzgerald, and whatever I saw fit to play from the rock world or from the classical catalogue." Spiced with Schwartz's idiosyncratic personal commentary, the program is now heard nationwide on XM Satellite Radio.

"Then I finished that part of my life," he says, referring to his singing, "and I gave the piano to my friend John Pizzarelli. He's a wonderful musician, and his wife, Jessica Molaskey, is a singer, so the piano is in good hands. I go to their house frequently, and there's the piano, and I feel delighted, as Arthur would have, too."

Friends and family are very much in evidence in the office, whose high ceilings leave enough wall space to accommodate plenty of books and CDs, as well as an enormous poster from the 1995 concert honoring Frank Sinatra that Schwartz hosted at Carnegie Hall. Near his desk he points out a photograph of his parents, looking young and glamorous; Katherine Carrington Schwartz shows no signs of the malignant hypertension that shadowed their marriage and killed her when Jonathan was 15. A portrait by Richard Avedon shows Schwartz with his former spouse, journalist Marie Brenner; their daughter, Casey; theater director Ellie Renfield, his wife since 1984; and their son, Adam.

Don't expect to read much about this 21st-century extended family in All in Good Time, however, even though it's dedicated to all four of them. Schwartz's memoir, published by Random House, frankly chronicles the impact of his mother's poor health, his loving but bumpy relationship with his father, bruising battles with his stepmother and several unhappy romances as he journeyed from lonely childhood through troubled adolescence and turbulent 20s while he sought to combine radio and writing in a single career. Brenner and Renfield appear on a single page that lists their professional credentials, marriage dates and children's births before ushering them off as "quite above the fray of these pages," which briefly reintroduce Casey and Adam at the Lincoln Center celebration of Arthur Schwartz's music in 2001 that movingly closes the book.

"These people populate my life intimately," Schwartz explains, speaking with the same controlled intensity—and dramatic pauses—familiar to his radio listeners. "They're good friends, we see each other all the time, we spend Christmas at Marie's. I don't want to intrude on them; they're my life's blood." Noting that the memoir deals more thoroughly with the first half of his life, more episodically with the years since the early 1970s, he says, "The getting there is lavished with a certain detail; it seemed a natural course of events. At one point I had this 550-page thing, so I cut it back and took out a lot. Fred Astaire once said to my father, 'You know, Arthur'—in that way he talked, with a friendly urgency— 'I start off with a 15-minute dance routine, then I cut and cut and cut until it's six and a half minutes and absolutely perfect... and then I take out two more minutes.' I had that in mind in cutting the book"

With a final page count of 304, All in Good Time is Schwartz's first full-length work of nonfiction. (A Sports Illustrated article about the Red Sox—Yankees 1978 playoff game was later published by Akadine Press under the title A Day of Light and Shadows, reissued last fall by the Lyons Press.) The protagonists of Distant Stations, The Man Who Knew Cary Grant and many of the stories collected in Almost Home (1970), however, share a good deal of their author's personal history, and the memoir contains several incidents, including a near-suicide and a stint in the Paine Whitney psychiatric clinic, that were used in Schwartz's earlier works wearing only the slightest of fictional disguises. What made him decide to throw off the disguise and write an actual autobiography?

"Jonathan Karp and Ann Godoff," he replies. "I had written a novel called The Paris Concert, it was given to Random House for their consideration, and Jonathan came to me and said, 'If you turn this into a memoir, we might pay you a little more money.' I had never thought to write at length in the first person—I'm a third-person, fiction kind of guy—but I thought about it, and then I wrote a nine- or 10-page memo about my intentions. As I did that, I discovered this was a feasible idea. They liked that memo and, as promised, gave me a little more money."

Not every author would freely admit to such pragmatic considerations. But All in Good Time is notable throughout for its candor: the vivid, nuanced character sketches of colleagues, friends and lovers are seldom entirely flattering; the portrait of his stepmother is grimly unforgiving; and Schwartz doesn't just acknowledge his own youthful pretensions and self-pity, he reproduces them uncensored in a few letters of the sort most of us would flinch to discover in our basements, let alone reprint for others to read.

He acquired his distaste for glossing things over at an early age, we learn from the memoir's account of his reaction to Night and Day, a 1946 biopic produced by Arthur Schwartz that sanitized family friend Cole Porter's life virtually beyond recognition. "I didn't think the movie was telling the truth. I felt that it was giving me the runaround," Schwartz writes. When he tentatively conveyed this opinion to his parents, they turned it into a cute story about how much "Jonno" loved the movie and his father. "Evasions like these were the currency of the family," the passage concludes, listing his mother's illness and his poor grades in school as other subjects that were never frankly discussed.

"Night and Day was famously ludicrous, and my father produced it: how could he have done it?" Schwartz muses nearly 60 years later. "To some degree he was a poseur; he was a Jewish boy out of Brooklyn who had a slight British accent. Seeing that film was a primitive epiphany—anything is primitive when you're eight years old. I had to find friends who could help me display the other side of the coin, friends like Jacob Brackman [movie critic for Esquire in the late '60s and lyricist for several of Carly Simon's early hits]. He was a wonderful writer and editor; a lot happened to me through editing, in Jake's hands and one or two others' hands. I was just simply taught to speak the truth; it was always in my heart, but I had come through—to say the least!—a theatrical childhood.

"Certainly I'm a theatrical kind of fellow; my enthusiasms are not subdued. But I tended to gravitate, however difficult the relationships were, to people who could teach me something, and that was smart of me. My friend Daphne Merkin [one of the dedicatees of The Man Who Knew Cary Grant] is a substantial figure in coming down hard when she sees something wrong. I call her way of editing 'edit-lunge': she'll lunge at me and say, 'Jonno, what were you thinking?' or, 'Jonno, are you crazy?' She goes for the stuff you admire and just scrapes it off the page. She's the efficient Mary Poppins who shows up and cleans up the room, viciously. Her hand is all over All in Good Time."

He never saw any conflict between his two creative interests, Schwartz declares. "From a very early age, I knew that I wanted to do two things: to be a writer and to do something on the radio. Television came along: wasn't interested. It was the magic of radio, and I thought I could do it all on one show, that everything was connected. There was a movie called My Foolish Heart, starring Susan Hayward, which spawned the song with the same name—well, without J.D. Salinger there's no song, because the movie is based on 'Uncle Wiggly in Connecticut.' One thing leads to another, it seems to me."

In fact, Schwartz's late-1960s broadcasts at WNEW-FM, a pioneering progressive rock station whose loose format gave him room to be himself on the air, prompted editor John Ware to remark, "He sounds like a writer," and to ask if he had anything to show Doubleday. Schwartz hightailed it to Ware's office with a sheaf of stories that had been published in Redbook, the Paris Review and other periodicals; Almost Home appeared in 1970. The collection's good reviews and surprising commercial success helped its author persuade station manager George Duncan to give him a Sunday-morning slot on WNEW-AM dedicated to the radical notion that there was an audience for high-quality American music from Sinatra to Sondheim and beyond, and that listeners might not mind the disc jockey talking about books or baseball as well. Sometimes synergy actually works.

But sometimes it doesn't. When Doubleday published Distant Stations in 1979, Schwartz recalls, "They had real hopes for it, and it got good reviews, but there was a paperback auction and no one bid. It was a major shock; I had to go back on the radio, which I didn't want to do. I never wanted to be a full-time writer, but had I gotten a big advance, I might have behaved differently toward making money and going to a job almost daily. My whole radio career might have been changed."

Instead, he kept his day job while continuing to write, and Doubleday publisher Sam Vaughan took Schwartz along when he went to Random House. "There we encountered the dread Joni Evans, now appropriately an agent," says the author, never one to mince words. "She was not at all interested in my little book of fiction." The Man Who Knew Cary Grant, unsurprisingly, did not sell well, but it solidified his relationship with Vaughan, "an older publishing generation guy, a sweetheart, a very significant and wonderful man. I used to read him long things I was writing over the phone." Schwartz now regrets not taking Vaughan's advice to make the interconnected stories charting the relationship between a theater lyricist/composer and his son into a novel, but he made partial amends by allowing the subtitle "A Novel" to appear on the cover of The Man Who Knew Cary Grant's paperback edition.

He has no further plans for The Paris Connection, which was "cannibalized" for All in Good Time, but he does intend to produce more novels. "It was enjoyable writing in the first person [in the memoir]; it gave me space that I don't have in the third person. I'd like to write a novel in somewhat of that voice. It gives me more tools, I can call upon the language in a more powerful way, it's less limiting and formal. I still have a couple of things that I'd like to talk about in fiction. In radio, I just want to keep doing what I'm doing. I'm left alone on XM Satellite, the management trusts me, and I have no trouble in presenting myself and my music in the way I want."