Halfway through my last memoir, my editor, Susan Kamil, said, “Maybe you should just move on. This isn’t working.”

I threw the phone across the room. I’d been working on the book for a couple of years, sending drafts back and forth to Susan. “I’m sorry,” she continued, “it’s good, but if you’re not willing to go deeper, there’s just no point.”

Susan Kamil never let you off the hook.

When Susan died on Sept. 8, there was an outpouring of grief from the entire publishing community. Susan was the most lovable person: enormously generous, endlessly kind, crazy for cats and great fun to be with. Always dressed in bluejeans and sneakers, she was one of the few women who was equally adored by both men and women. A gifted publisher, she was also a wonderful boss. But above all, Susan was an editor.

[ Read our obituary of Susan Kamil. ]

Susan didn’t just read your manuscript and offer suggestions; she became your collaborator, your partner. With Susan, a book was an ongoing conversation, and she filled every page of every manuscript with questions, suggestions, comments. The process never ended: She kept fretting over the words until the book went to press. She couldn’t help herself. In Susan’s mind a book was never really finished, and I suspect she found it impossible to read even the dustiest, most ancient tome without a pencil in her hand.

CreditRandom House, via Associated Press

Months after I had finished my first novel, long after it had been accepted, paid for and copy-edited, Susan called. By then I was at a rural writers’ colony, deep into my next book and the phone reception was poor. “I’ve been worrying about that first chapter,” she said.

“What?” The phone crackled and I wasn’t sure I’d heard her right.

“I think you need to rewrite it.” It made me crazy, but I never doubted Susan’s instincts. I spent the next month reworking Chapter 1.

And there she was again, true to form, calling long after she’d accepted my last memoir. “You’re not going to want to hear this …” she began.

My heart stopped. This, after all, was the book she had once suggested I abandon. Was she having second thoughts? “I just read it again,” she said. How many times, I wondered, had she pored over those pages? 10? 20? “And I get the feeling that right after Chapter 20, there’s something else you want to say.”

How had she known that? I’d discarded the idea; it was too much, too intimate.

“Write that chapter!” she said. “There’s time. The book needs it.”

And of course I did.

Susan’s ability to read my mind astonished me; our editing sessions often felt like a visit to a psychiatrist. I’d arrive at her cluttered office every few months to find my latest pages sitting in the middle of her desk, covered with pencil scrawls and festooned with little yellow Post-its. We’d pull up chairs, eat lunch (always sushi), chat about our families. Then we’d push the plates away and go through the manuscript page by page. Susan would lean across the desk, fix those large expressive eyes on me, point at a paragraph. “Are you sure he’d do that?” “What are you really trying to say here?” “I have a feeling you don’t like this woman. Can you put it into words?” Answering her questions, I’d find myself saying things I hadn’t even known I thought.

The process never changed: Memoir or novel, it was exactly the same. Even fictional characters were so real to Susan that she wanted to know what they were feeling, doing, wearing, even when they stepped off the page.

A few years ago, as we were working on the final draft of my novel, Susan stopped at a crucial moment and asked what a minor character was thinking. I said I didn’t know.

“Of course you do,” she replied. And just like that I saw the scene, heard the dialogue. It was so vivid that I picked up my computer, found an empty desk and spent the next half-hour putting it all down. When I went back to Susan’s office, she read the pages and said triumphantly, “I knew you knew.” But the truth is that I don’t think it would have come to me had Susan not pushed so hard, been so relentless.

These marathon sessions lasted several hours and often sent me straight back to zero. But no matter how brutal the process, I always left in a state of euphoria, itching to get back to work. Susan’s greatest gift was her ability to make you believe in yourself. “It’s going to be a wonderful book,” she’d say as you walked out the door. “I can’t wait to read it.”

I’ve saved piles of Susan’s manuscript notes, because they’re such a fascinating example of how an editor shapes a book. “It’s like a master class in writing,” I told her. She shot me a derisive look: “Please. I’m just doing my job. You’re the writer.”

I don’t think this was false modesty. Despite her powerful job and enormous reputation, Susan never lorded it over you. And while many editors secretly yearn to write, Susan had no desire to see herself in print. Even when she wrote promotional matter — flap copy, catalog material — she’d call and say “Will you take a look? I’m no writer.”

But she was a reader, in the fiercest sense. Susan knew exactly what she wanted. When I finished my last book, she said, “I love that Paris chapter. I want more. Could you please turn it into a novel?” She said it again and again, so often that I began writing the book in my head. Last month, when Susan fell ill, I asked what I could do for her. The reply came shooting back: “The best gift would be to write me that book.”

What else could I do? I called it Susan’s book, anticipating the joy of working together when she was better.

It was going well, but at the moment the characters and I are feeling utterly lost.

Ruch Reichl is the author of “Save Me the Plums: My Gourmet Memoir.”

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