Siegfried "Zig" Engelmann (November 26, 1931 – February 15, 2019)[1] was an American educationalist who co-developed the approach to instruction termed "Direct Instruction" (DI). Engelmann was Professor Emeritus of Education at the University of Oregon and Director of the National Institute for Direct Instruction.[2] He wrote more than 100 curricula using DI principles and numerous other books and articles.[3]