I've just finished reading Paul Rand - Conversations with students. It was recommended by Josh Brewer in his Build 2011 presentation and i've just got round to reading it.
As you might expect from Rand it's scattered with pearls of design wisdom. It's a lightweight book and beautifully designed. However the verbatim replay of discussions is often more "errr you know" or "well i'm not sure, errr where were we?" than coherent views of a master designer.
Some of my favourite snippets:
"Design is relationships. Design is a relationship between form and content"
"The reason people want to come put of (a grid) is because they don't know what they are doing when they are in it."
"This is exactly the meaning of design; it is the conflict between form and content, form being the problem"
"You will learn (to do) most things by looking, but reading gives understanding. Reading will make you free"