First published in 1983. Routledge is an imprint of Taylor & Francis, an informa company. This monograph is a review of the evolution of George Briggs’ informationprocessing model from a general schema beginning with the work of Saul Sternberg (1969a) and Edward E. Smith (1968) to a fairly well-detailed schematic representation of central processes that Briggs was working on at the time of his early death. The development of Briggs’ model of the binary classification task (BCT) spanned the period from 1969 when he published his first report on choice reaction time with Blaha (Briggs & Blaha, 1969) to 1977 with the publication of a posthumous paper (Briggs, Thomason, & Hagman, 1978). The model evolved across a total of 16 experimental and 2 review papers.