Updated for 2015, the second edition of Introduction to Astrodynamic Reentry continues my tradition of teaching atmospheric entry from an analytical perspective, with finding closed-form solutions being the preferred approach. The over-arching goal is to instill an understanding of how "families of solutions" behave as well as the general trends, tradeoffs, and nature of atmospheric entry. My approach is to use easily visualized variables to solve the analytical problems first and keep them (more-or-less) consistent as we move to the computer for the harder problems. This is a "back to the basics" approach for a new generation of students who've become more comfortable with numerical solutions than analytical ones. The pages are loaded with equations because I've included the details of most of the derivations. This book pulls together many classical analyses and presents them in a consistent notation for the first time. It provides a convenient starting point for an analytical understanding of atmospheric entry, with plenty of references to those original works. It ties together results that were originally published years apart by different authors. And, peppered throughout, you'll find some new approaches and results.