While suffering from a bad case of writer’s block in early 1945, Mary Lou Williams turned to a book about astrology for inspiration. She quickly realized that the personalities traits denoted by each sign of the Zodiac could be a jumping-off point to draw a series of character sketches in music. Each piece was inspired by a famous friend in the jazz world. For example, “Aries” was the sign of Ben Webster and Billie Holiday. “Changeable, moody, and impulsive,” Williams later explained, “they seemed to me the examples I should choose for my composition.” Libras love beauty and art, therefore Williams wrote that one with Art Tatum in mind. Sagittariuses are said to be noble, successful, and magnanimous, which made Williams think of producer John Hammond. While the concept makes for an intriguing bit of personal history, the joy of Zodiac Suite doesn't depend on its concept. The song cycle inhabits a variety of moods, from playful to mournful, and the small-trio setting makes the music feel especially intimate, almost as if it were improvised especially for the listener in the lamp-lit comfort of a small New York City apartment.