The letters reprinted in chronologic order with minimal annotations were selected and edited by Matie Molinari, Corinne McLuhan and William Toye. They provide a background to McLuhans's life and intellectual growth and reveal his staggering knowledge of the literature of the great writers and thinkers who inspired him to achieve his penetrating insights into the age of electronic communication and become its most renowned interpreter. -- Source of annotation: Marvin or Ruth Sackner.

Kostelanetz writes that "this book differs from most other writing about Cage in emphasizing his professional adventurousness, acknowledging not only his music but his theater, writing, radio, visual art, political philosophy, and much else, all reflecting a career based upon artistic (and thus artists') freedom...In its variety and its departures from expository conventions thirty Years is probably a more Cagean book than a measured continuous exposition." The design of this book utilizes page numbering through overlaying each page of text with a large gray number. -- Source of annotation: Marvin or Ruth Sackner.