This is an authoritative and accessible guide to modern ideas in the broad interdisciplinary fields of cultural and critical theory that have developed from interactions among different modern traditions of thought.
For those of you in grad school or soon to be headed that way, I would highly recommend A Dictionary of Critical and Cultural Theory published by Blackwell. It was first published in 1997 and I don't know if there has been a second edition, but this was an invaluable resource for me during my grad years. It is a true dictionary and not very portable, but I found its depth to be more useful than some of the other more concise editions. It doesn't have everything, not that any volume does, but I usually found what I needed to know and then some with this resource.