Do the Jack Reacher books need to be read in order?

You do not need to read the Jack Reacher books in order, and you do not need to start at the beginning. You can enjoy the books just as much by jumping around the set order, due to the fact that the novels themselves jump around in time.

For example, the series' most recent book, "The Affair," starts at a major point in Reacher's military career, which comes six months before the first book, "Killing Floor," takes place. However, if you have a chance to read the books in order then there is no reason not to, as that is how the books were designed.