Being and Nothingness may well be thought of as Sartre's greatest work; it has also come to be regarded as a text-book of existentialism itself, and this is for many reasons a proper way to read it. These pages set out with relative perspicuity almost all of the salient ideas of existentialism; and, in addition, the method according to which the book is composed is itself highly characteristic of existentialist philosophers.
From the Introduction by Mary Warnock