Coincident with the publication of the Senses, Gibson began the “Purple Perils” (The “Purple Perils” were short manuscripts printed in purple ink). For his perception seminar at Cornell, Gibson would write notes, usually a few pages in length, on a variety of topics and distribute them for discussion. Most of the material in these notes never reached publication in the form they were written in, but they served as the foundation for publications submitted in the late 1960s and the 1970s. They were especially relevant to the germination and development of Gibson’s final book, The Ecological Approach to Visual Perception (1979). In this chapter I overview the “Purple Perils” (hereafter “PP”) which number over 100 and constitute a book in themselves. I do not review the entire set of “PP”; I have instead selected what seems to be a representative group, trying to include most of the noteworthy ones.