This work is a compilation of Ronald Searle's St. Trinians cartoons together with contributions from all sorts of eminent literary and musical folk about the awful girls. Kaye Webb, Searle's wife at the time of publication, deserves the primary author position: she compiled and edited the book as well as writing the introduction. A good selection of Searles cartoon's are there, but he did none of the writing. The book was first published by Perpetua in 1959 and later by Penguin Books in 1961.
The story of Searle's abandonment of Webb and their teenage children is well known - it happened around the time of the Penguin issue.