Ward is co-author, along with astronomer Donald Brownlee, of the best-selling "Rare Earth: Why Complex Life Is Uncommon in the Universe", published in 2000.
В соавторстве с Дональдом Браунли () Уорд написал книгу "Rare Earth: Why Complex Life Is Uncommon in the Universe", ставшую впоследствии бестселлером.