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Web Design Essentials
Don't Make Me Think!: A Common Sense Approach to Web UsabilityDon't Make Me Think!: A Common Sense Approach to Web Usability by Steve Krug
Buy new: £12.46 / Used from: £9.90
Let's face it people if you're not testing your websites you're making rubbish websites. Find out how to test your website effectively with real people.
Homepage Usability: 50 Websites DeconstructedHomepage Usability: 50 Websites Deconstructed by Jakob Nielsen
Buy new: £15.49 / Used from: £4.66
When your boss asks you to do something stupid on the company website, this book is your best defense.
Designing Web Usability: The Practice of SimplicityDesigning Web Usability: The Practice of Simplicity by Jakob Nielsen
Buy new: £17.49 / Used from: £2.11
Nielsen is the king people, All web designers should read this.
Building Accessible WebsitesBuilding Accessible Websites by Joe Clark
Buy used from: £18.00
The most comprehensive guide to making your websites accessible - which you ought to at least attempt.
Bulletproof Web Design: Improving Flexibility and Protecting Against Worst-Case Scenarios with XHTML and CSSBulletproof Web Design: Improving Flexibility and Protecting Against Worst-Case Scenarios with XHTML and CSS by Dan Cederholm
Buy new: £24.64 / Used from: £7.75
Dan Cederholm tells you everything you need to know about designing.
Designing with Web Standards (Voices That Matter)Designing with Web Standards (Voices That Matter) by Jeffrey Zeldman
Buy new: £15.99 / Used from: £9.97
'99.9% of websites are obsolete'. This tells you why - it'll help to explain to your boss as well.