Being Digital The book that started it all for me - the principles of digitisation are still as true as ever.
The Cluetrain Manifesto Conversations rule.
Don't Make Me Think: A Common Sense Approach to Web Usability Brilliantly designed and written book on usability in its widest sense.
The Design of Sites: Patterns for Creating Winning Web Sites Do not let clients see this book. It's the secret manual.
Permission Marketing: Turning Strangers Into Friends And Friends Into Customers The original 'Seth' - a classic on respectful marketing.
Made to Stick: Why some ideas take hold and others come unstuck Make your ideas sticky. Awesome book.
A Whole New Mind: Why Right-Brainers Will Rule the Future If you're creative in any way (and aren't we all) this book will make you feel ace.
Dark Angels: How Writing Releases Creativity at Work Great book on writing like a real person at work.
Understanding Comics: The Invisible Art So much amazing stuff in here. If you think comics are irrelevant you need this most of all.
The Book of Gossage: A Compilation-Which Includes "Is There Any Hope for Advertising?" Expensive and normally only available second-hand. But worth every penny. Seminal.