"Design of 'The Elements of Style' by Strunk, White, and Kalman
(Penguin Press, 2005)
Perhaps part of Strunk and White’s intent was a useful manual of usage and style, and they did this in almost militant fashion (but not without their own clever humor), it was Maira’s idea to illustrate all this, and it was our job to keep one eye on the usefulness, and serve Maira’s wondrous and unorthodox approach to telling stories.
Design: Peter Buchanan-Smith, Maira Kalman"
From Buchanan-Smith, here and here