Twenty-Four Hours A Day is a 1954 book written by Richmond Walker (1892-1965), is a book that offers daily thoughts, meditations and prayers to help recovering alcoholics live a clean and sober life. In Alcoholics Anonymous literature Walker became the second most popular A.A. author in total book sales, second only to Bill W. It was often referred to as "the little black book" due to its black cover in the 1960s.