A Course in Miracles (also referred to as ACIM or the Course) is a 1976 book by Helen Schucman. The underlying premise is that the greatest "miracle" is the act of simply gaining a full "awareness of love's presence" in a person's life. Schucman said that the book had been dictated to her, word for word, via a process of "inner dictation" from Jesus Christ. The book is considered to have borrowed from New Age movement writings.

ACIM consists of three sections: "Text", "Workbook for Students", and "Manual for Teachers". Written from 1965 to 1972, some distribution occurred via photocopies before a hardcover edition was published in 1976 by the Foundation for Inner Peace. The copyright and trademarks, which had been held by two foundations, were revoked in 2004 after lengthy litigation because the earliest versions had been circulated without a copyright notice.

Throughout the 1980s, annual sales of the book steadily increased each year; however, the largest growth in sales occurred in 1992 after Marianne Williamson discussed the book on The Oprah Winfrey Show, with more than two million volumes sold. The book has been called everything from "New Age psychobabble" to "a Satanic seduction" to "The New Age Bible". According to Olav Hammer, the psychiatrist and author Gerald G. Jampolsky was among the most effective promoters of ACIM. Jampolsky's first book, Love is Letting Go of Fear, which is based on the principles of ACIM, was published in 1979 and, after being endorsed on Johnny Carson's show, went on to sell over three million copies by 1990.