Structural proof theory is a branch of logic that studies the general structure and properties of logical and mathematical proofs. This book is both a concise introduction to the central results and methods of structural proof theory, and a work of research that will be of interest to specialists. The book is designed to be used by students of philosophy, mathematics, and computer science. A special feature of the volume is a computerized system for developing proofs interactively, downloadable from the web and regularly updated.
Rigorous and thorough discussion of sequent calculus, natural deduction, and the relations between them. I once had the pleasure of meeting Sara and she had a strong preference for detailed proofs, so sometimes the proofs pedantically detailed, which I like very much. It's much better than proof by intimidation -- we all come across a difficult 'proof is left as an exercise' every now and then, right? I do not consider myself a proof theorist, but a thorough study of this book might make me one (I did not close-read this time). I like the writing better than Basic Proof Theory, so I would recommend it.