Jeffrey Zeldman is the founder of Happy Cog design studios, cofounded An Event Apart and wrote Designing With Web Standards, published A Book Apart & A List Apart as well as host of The Big Web Show.
Content precedes design.
Design in the absence of content is not design, it's decoration.
Don’t design to prove you’re clever.
Design to make the user think she is.
90 percent of design is typography.
And the other 90 percent is whitespace.
Style without purpose is noise.
Speed is to today’s design what ornament was to yesterday’s.