Just when one thinks every topic has been covered to the fullest, somehow, talented writers, creative artists, and forward-thinking editors come up with new takes and fresh angles. This is particularly true of the books selected as the best of 2009. The hallmarks of the nonfiction this year include some unusual scientists, from two brothers who invented day-glow paint, to a scientist tracking snow leopards in Mongolia. New heroes and events arise from the Civil Rights Movement, with untold stories from lesser-known people, and the Darwin bicentennial garnered some particularly impressive titles. Thoughtful writers of history continue to present the past in a manner that is accessible and thought-provoking. Fantasy continues to have a stronghold on the reading interests and imaginations of children and young adults, but this year's list has some terrific genre-bending titles and mash-ups to add to the mix. The best of the fiction is original and/or timely, ranging from an eco-mystery, the effects of carbon rationing on life in the future, and a totally new spin on the tired undead theme. The 54 books annotated in this article were selected as the best of the year from the 5,700 books reviewed in this journal's pages in 2009.