Draft is a series about the art and craft of writing.

Authors ­are often asked where they get their ideas. As a writer for hire, my answer owes something to the songwriter Sammy Cahn. Asked which came first, the music or the lyrics, he said: “The phone call.”

One morning that call came from a rabbi in the Midwest who knew of my work as a ghostwriter. He asked if I had any interest in writing a memoir with the patriarch of a prominent and philanthropic family. There was a twist: This book would never be published.

It took time to absorb the oddness of the question. Was I really willing to write a book that wouldn’t be seen (let alone read) by anyone I knew, or anyone who might want to hire me in the future? And was I prepared to forgo royalties, reviews and the assorted social and economic benefits that authors like to dream about and sometimes even experience? The client’s family had an excellent reputation, so I flew out to see him.

I met J. and his wife for dinner in a downtown restaurant, and we liked one another immediately. We met again the next morning, and his son and I soon came to terms in a pattern I would see again. Members of the older generation are often reluctant to spend money on a memoir until a son or daughter points out that a private book is really for the grandchildren — and eventually for their children. Talk about legacy! In other words, Dad (or Mom), although this book is about you, it’s not really for you.

A few months into the project, J. had a fatal heart attack. When his widow asked me to keep writing, I began turning a memoir into a biography. By then I had learned that J.’s father had also written a private memoir, and so had his father, so the book I was writing would serve as another link in a continuing and treasured family chain.

In most respects, writing for private clients is like working on any other book. One difference, though, is that instead of trying to imagine what my audience might find compelling, or debating some of the contents with editors and publishers, I now had a direct line to the readers. They were the same people I was interviewing — my client’s family members and his close friends and associates, so I knew what mattered to them.

Another happy surprise was that private books don’t demand complete structural consistency. When an occasional topic cries out for a different approach — a few pages of oral history, perhaps, or even an annotated list — I feel free to make the form fit the content, rather than the other way around. There are times, for example, when the best way to handle a complicated or controversial subject is to present an edited conversation that reflects several viewpoints. I don’t take these liberties often, but it’s nice to have options.

After writing half a dozen books that can’t be found in any library or bookstore, I’ve found rewards that mean as much to me as seeing my name on the best-seller list. Often, publishers of commercial memoirs or biographies encourage the writer to pay special attention to the sordid elements of a life, because, let’s face it, scandal, crime, addiction and other human failings are more compelling to most readers than the values I’m likely to be writing about. But when a family or an organization commissions a book, they’re more interested in stories, personalities and lessons, rather than adversarial journalism or sensationalism. They assume the writer will focus on the subject’s better nature, which is fine by me. St. Augustine notwithstanding, not every memoir has to be confessional, and no rule, heavenly or human, requires us to disclose every detail of our lives. Call me old-fashioned, but I’d rather explore the qualities and actions that will inspire future generations. Chances are, they will also inspire me.

But isn’t this just public relations? I don’t think so — not when your book will be read by only a handful of readers. Call it private relations, if you like. In commercial memoirs, of course, I do my best to present a full picture of the person, which can be difficult when he or she has spent a lifetime avoiding certain topics.

Private books present a different set of challenges. My phone doesn’t ring as often, and when it does, I can’t show my past work to potential clients because private books are, by definition, confidential. I don’t enjoy having little to say when somebody asks what I’m working on, and when I run into problems, there is no editor to consult with. I miss the advice and friendship of publishers, editors and publicists, and the simple thrill of walking into a publishing house, where the walls are lined with shimmering new books and the offices are filled with people who love them.

Among my commercial books, two or three sold so poorly that they might as well have been issued privately. But I’ve also been surprised in the other direction. I spent several years on a private book that ended in a print run of 100,000, which calls into question the very notion of “private.” I was asked to help the founder of a cable company write his memoirs, but he was so modest, so eager to give credit to others, that I soon approached his son with a different idea: “What if I wrote a personal history of the company that will include as much about your father as he’ll tell me?” This made it possible for the founder’s colleagues to describe his many accomplishments and acts of kindness. When the book was done, the company produced copies for its many employees.

But that’s unusual, and the other private books I’ve written have remained virtually invisible. Two of the most meaningful were memorials for cherished family members, both of whom were leaders in their community and powerful forces for good. There’s some truth to the notion that a biography can bring a person back to life. Neither of these memorials has even been printed, let alone distributed. But to the families, they mean the world.

William Novak co-wrote the memoirs of Lee Iacocca, Magic Johnson, Oliver L. North, Thomas P. O’Neill Jr., Nancy Reagan and Tim Russert, among others.