This book is a collection of notes and unpublished results which I have accumulated on the subject of classical field theory. In 1996, it occurred to me that it would be useful to collect these under a common umbrella of conventions, as a reference work for myself and perhaps other researchers and graduate students. I realize now that this project can never be finished to my satisfaction: the material here only diverges. I prefer to think of this not as a finished book, so much as some notes from a personal perspective.

In writing the book, I have not held history as an authority, nor based the approach on any particular authors; rather, I have tried to approach the subject rationally and systematically. I aimed for the kind of book which I would have appreciated myself as a graduate student: a book of general theory accompanied by specific examples, which separates logically independent ideas and uses a consistent notation; a book which does not skip details of derivation, and which answers practical questions. I like books with an attitude, which have a special angle on their material, and so I make no apologies for this book's idiosyncrasies.

Several physicists have influenced me over the years. I am especially grateful to David Toms, my graduate supervisor, for inspiring, impressing, even depressing but never repressing me, with his unstoppable ‘Nike’ philosophy: (shrug) ‘just do it’. I am indebted to the late Peter Wood for kind encouragement, as a student, and for entrusting me with his copy of Schweber's now ex-masterpiece Relativistic Quantum Field Theory, one of my most prized possessions.