Don't Make Me Think!: A Common Sense Approach to Web Usability
Steve Krug

£22.18

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This book is well written, short, and clear.

It has reassured me about much of what I do - and given me some pointers for areas I can improve on.

One of the great things about this book is the way it addresses the combination of technical and political issues that web projects can get bogged down in - it has a nice section called "Help my boss wants me to ___" with some good sample letters to the boss.

It really brings home that conventions are useful - and you need to test the site on users - little and often.