Getting Real is the undisputed bible of agile software development—a manifesto that can change your view in a single reading. However when it comes to typography and design, the closest I have ever come to such a document was Mark Boulton’s Better Typography presentation. Now there’s a contender:
The Vignelli Canon (pdf)
I can’t do this tome justice. Split into two parts—The Intangibles (semantics, syntactics, etc.) and The Tangibles (paper sizes, grids, type sizes, etc.)—Massimo Vignelli’s book covers everything you could want to know about typography in graphic design.
One definitely not to miss.
How Do You Design? (pdf)
Hugh Dubberly’s book looks at “over one-hundred descriptions of design and development processes, from architecture, industrial design, mechanical engineering, quality management, and software development”.
By reading this you can’t fail to learn something about design.