Amy Tan has built a reputation on novels like 'The Joy Luck Club' and 'The Kitchen God's Wife' that explore the immigrant experience and deep personal relationships. In the spring of 2011, while circulating a two-page proposal for her new book, she was searching for a defining relationship of her own.

'I finally realized I needed an editor,' she said.

From the publication of her first book in 1989 onward, Ms. Tan, 61, worked closely with Faith Sale, a well-known editor at G.P. Putnam's Sons, now part of Penguin Group. When Ms. Sale died of cancer in 1999 at age 63, Ms. Tan was suddenly left without her longtime reader, editor and friend.

For years, she was 'unable to really find a replacement. I just couldn't -- I couldn't bear to,' says Ms. Tan, who also lost her mother a few weeks before Ms. Sale's death.

'The Valley of Amazement,' out Tuesday from HarperCollins, tells the story of a half-American, half-Chinese woman who becomes a celebrated courtesan in Shanghai in the early part of the 20th century. With its sweeping, multigenerational portraits of mother-daughter relationships in a detailed historical setting, the book marks a return for Ms. Tan to the themes and style she became famous for in her first novel, 'The Joy Luck Club,' still her biggest commercial success.

Ms. Tan has sold an estimated five million copies of her books world-wide, according to her agent, Sandra Dijkstra.

She stayed at Putnam through the publication of 'The Bonesetter's Daughter' in 2001, and her last book, 'Saving Fish From Drowning,' in 2005, but she felt less of a connection without Ms. Sale there to read her work.

'There was somebody there, but nobody really sat down and read the book and said 'Here's what you should do,'' she said. 'They would have given me an editor, but I just couldn't make up my mind. And I just thought, I can never replace Faith.'

A spokeswoman for Putnam said that Ms. Tan was assigned an editor for 'Saving Fish From Drowning,' but 'Faith Sale was a legend in the business -- a one-of-a-kind editor, and her death was devastating for everyone.'

Ms. Sale, whose career spanned four decades, was known in publishing circles for her hands-on editing style and refinedliterary sensibilities. In addition to Ms. Tan, she also edited works by authors including Donald Barthelme, Kurt Vonnegut and Joseph Heller.

Narrated by a ghost, and lacking a central mother-daughter narrative that has become a hallmark of her work, 'Saving Fish from Drowning' was a departure for Ms. Tan. It was met with mixed reviews.

'It's a very different book for Amy,' Ms. Dijkstra said of the 2005 novel. 'I think people feel she's been away.'

By 2011, with the central idea of 'The Valley of Amazement' in mind, Ms. Tan said she was ready to look for a new editor. 'I told my agent . . . I don't care what the amount of money is, I want an editor. I want the best editor for myself,' she said. Ms. Dijkstra sent out a short synopsis of the idea to select publishers.

Daniel Halpern, editor and president and publisher of Ecco, an imprint of HarperCollins, was among the interested parties. A poet himself and editor for writers including Richard Ford and Joyce Carol Oates, Mr. Halpern had been friends with Ms. Tan's previous editor and had long admired the author's work. When 'The Valley of Amazement' proposal came his way in 2011, he jumped at the opportunity.

Mr. Halpern was persistent. In addition to HarperCollins (a unit of News Corp, which also owns Dow Jones & Co., publisher of The Wall Street Journal), Ms. Tan and her agent were facing offers from other publishers. When he sent Ms. Tan an email asking if she could offer any more thoughts on what her new book would be about, she sent back a 4,000-word response explaining why she doesn't like to write synopses of her novels. He was thrilled, and told her she should publish it as an essay.

When Mr. Halpern met Ms. Tan in person in New York, along with her husband and her Yorkie, he gave her a mocked-up jacket of the book. He called her agent repeatedly to check in on the decision. 'My husband thought I had a lover,' said Ms. Dijkstra.

'I just felt such rapport with her, and you put a lot of emotionalenergy into these auctions,' said Mr. Halpern. 'If you end up not getting the book, it's really like a punch in the stomach.'

He was 'like a guy who wants you out on a date and you say, well I don't know,' says Ms. Tan. 'I was so uncertain -- it's kind of like getting married.' Ultimately, his enthusiasm prevailed and they signed a one-book deal. They have since signed a contract for a new novel and a book of essays.

One of the first things Mr. Halpern did when he received the full draft of 'The Valley of Amazement' was make a timeline of the entire novel, with notes on each individual character. He also made comments on the story and chapter-by-chapter notes.

He suggested altering the opening, so that the story began with the characters in the courtesan house in the early 1900s, instead of later in the plot. He worked with Ms. Tan on developing the narrator, Violet, who seemed 'thin' to him in the beginning. 'I remember saying to her, 'You've got to add flesh onto this woman,'' he said, 'I mean, who is she really?'

'There are writers you don't really ever establish that kind of a relationship with. It's not helpful to them and it's not something they want. They want to be left alone, and that's fine,' said Mr. Halpern.

'[With Ms. Tan] I always had the feeling that the more I said, the better. She wanted to hear everything.'

'The Valley of Amazement' contains Ms. Tan's first explicitly written love scenes, and she says she relied on Mr. Halpern to steer her away from 'anything that sounded corny.'

Mr. Halpern didn't recall making many cuts to the love scenes. 'I think she felt it was more sexual than I did,' he said. 'They were tender scenes, but they weren't graphically or wildly sexual.'

'She would argue with certain things, like, 'Well why is this? Why did that bother you?'' he said. 'That's the fun of it -- the back and forth.'

Ms. Tan said she was willing to 'cut pages without any qualms.'