For four years the Complex Systems Summer School has contributed greatly to education and research into complex systems. 1991 Lectures in Complex Systems presents a wide array of topics in the field, including neural network models for pattern recognition, pattern formation in biological systems, artificial life, ordering condensed matter, fractal time dynamics, cellular automata, complex pattern recognition, and random boolean networks. This book is a compilation of many of the lectures and contributions of the 1991 Complex Systems Summer School, and compliments the previous volumes in this series, Lectures in the Sciences of Complexity edited by Daniel Stein, 1989 Lectures in Complex Systems edited by Erica Jen, and 1990 Lectures in Complex Systems edited by Lynn Nadel and Daniel Stein.