- PETER McWILLIAMS has been writing about his passions since 1967. In that year, he became passionate about what most seventeen-year-olds are passionate about—love—and wrote Come Love With Me & Be My Life. This began a series of poetry books which have sold nearly four million copies.
- Along with love, of course, comes loss, so Peter became passionate about emotional survival. In 1971 he wrote Surviving the Loss of a Love, which was expanded in 1976 and again in 1991 (with co-authors Melba Colgrove, Ph.D., and Harold Bloomfield, M.D.) into How to Survive the Loss of a Love. It has sold more than two million copies.
- He also became interested in meditation, and a book he wrote on meditation was a New York Times bestseller, knocking the impregnable Joy of Sex off the #1 spot. As one newspaper headline proclaimed, MEDITATION MORE POPULAR THAN SEX AT THE NEW YORK TIMES.
- His passion for computers (or more accurately, for what computers could do) led to The Personal Computer Book, which Time proclaimed "a beacon of simplicity, sanity and humor," and the Wall Street Journal called "genuinely funny." (Now, really, how many people has the Wall Street Journal called "genuinely funny"?)
- His passion for personal growth continues in the ongoing LIFE 101 Series. Thus far, the books in this series include
- LIFE 101: Everything We Wish We Had Learned About Life In School—But Didn't (a New York Times bestseller in both hardcover and paperback);
- DO IT! Let's Get Off Our Buts (a #1 New York Times hardcover bestseller);
- LOVE 101: To Love Oneself Is the Beginning of a Lifelong Romance.
- His passion for visual beauty led him to publish, in 1992, his first book of photography, PORTRAITS, a twenty-two-year anthology of his photographic work.
Personal freedom, individual expression, and the right to live one's own life, as long as one does not harm the person or property of another, have long been his passions. He wrote about them in the 1993 book (revised in 1996) Ain't Nobody's Business if You Do: The Absurdity of Consensual Crimes in Our Free Country.- In 1994, after successfully being treated for depression, he wrote with Harold Bloomfield, M.D., How to Heal Depression. This was followed by their Hypericum (St. John's Wort) and Depression, all about treating depression with a natural herb.
- All of the above-mentioned books were self-published and are still in print.
- Peter McWilliams has appeared on The Oprah Winfrey Show, Larry King (both radio and television), Donahue, Sally Jessy Raphael, and, a long time ago, the Regis Philbin Show (before Regis met Kathie Lee—probably before Kathie Lee was born).